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J W T Hessels - One of the best experts on this subject based on the ideXlab platform.

  • simultaneous x ray and Radio observations of the repeating fast Radio Burst frb 180916 j0158 65
    The Astrophysical Journal, 2020
    Co-Authors: P Scholz, J W T Hessels, L G Spitler, A Cook, Marilyn Cruces, V M Kaspi, Walid A Majid, A Naidu, Aaron B Pearlman, Kevin Bandura
    Abstract:

    We report on simultaneous Radio and X-ray observations of the repeating fast Radio Burst source FRB 180916.J0158+65 using the Canadian Hydrogen Intensity Mapping Experiment (CHIME), Effelsberg, and Deep Space Network (DSS-14 and DSS-63) Radio telescopes and the Chandra X-ray Observatory. During 33 ks of Chandra observations, we detect no Radio Bursts in overlapping Effelsberg or Deep Space Network observations and a single Burst during CHIME/FRB source transits. We detect no X-ray events in excess of the background during the Chandra observations. These non-detections imply a 5 sigma limit of <5 x 10(-10)erg cm(-2)for the 0.5-10 keV fluence of prompt emission at the time of the Radio Burst and 1.3 x 10(-9)erg cm(-2)at any time during the Chandra observations. Given the host-galaxy redshift of FRB 180916.J0158+65 (z similar to 0.034), these correspond to energy limits of <1.6 x 10(45)erg and <4 x 10(45)erg, respectively. We also place a 5 sigma limit of <8 x 10(-15)erg s(-1) cm(-2)on the 0.5-10 keV absorbed flux of a persistent source at the location of FRB 180916.J0158+65. This corresponds to a luminosity limit of <2 x 10(40)erg s(-1). Using an archival set of Radio Bursts from FRB 180916.J0158+65, we search for prompt gamma-ray emission in Fermi/GBM data but find no significant gamma-ray Bursts, thereby placing a limit of 9 x 10(-9)erg cm(-2)on the 10-100 keV fluence. We also search Fermi/LAT data for periodic modulation of the gamma-ray brightness at the 16.35 days period of Radio Burst activity and detect no significant modulation. We compare these deep limits to the predictions of various fast Radio Burst models, but conclude that similar X-ray constraints on a closer fast Radio Burst source would be needed to strongly constrain theory.

  • simultaneous x ray and Radio observations of the repeating fast Radio Burst frb 180916 j0158 65
    arXiv: High Energy Astrophysical Phenomena, 2020
    Co-Authors: P Scholz, J W T Hessels, L G Spitler, A Cook, Marilyn Cruces, V M Kaspi, Walid A Majid, A Naidu, Aaron B Pearlman, Kevin Bandura
    Abstract:

    We report on simultaneous Radio and X-ray observations of the repeating fast Radio Burst source FRB 180916.J0158+65 using the Canadian Hydrogen Intensity Mapping Experiment (CHIME), Effelsberg, and Deep Space Network (DSS-14 and DSS-63) Radio telescopes and the Chandra X-ray Observatory. During 33 ks of Chandra observations, we detect no Radio Bursts in overlapping Effelsberg or Deep Space Network observations and a single Radio Burst during CHIME/FRB source transits. We detect no X-ray events in excess of the background during the Chandra observations. These non-detections imply a 5-$\sigma$ limit of $<5\times10^{-10}$ erg cm$^{-2}$ for the 0.5--10 keV fluence of prompt emission at the time of the Radio Burst and $1.3\times10^{-9}$ erg cm$^{-2}$ at any time during the Chandra observations at the position of FRB 180916.J0158+65. Given the host-galaxy redshift of FRB 180916.J0158+65 ($z\sim0.034$), these correspond to energy limits of $<1.6\times10^{45}$ erg and $<4\times10^{45}$ erg, respectively. We also place a 5-$\sigma$ limit of $<8\times10^{-15}$ erg s$^{-1}$ cm$^{-2}$ on the 0.5--10\,keV absorbed flux of a persistent source at the location of FRB 180916.J0158+65. This corresponds to a luminosity limit of $<2\times10^{40}$ erg s$^{-1}$. Using Fermi/GBM data we search for prompt gamma-ray emission at the time of Radio Bursts from FRB 180916.J0158+65 and find no significant Bursts, placing a limit of $4\times10^{-9}$ erg cm$^{-2}$ on the 10--100 keV fluence. We also search Fermi/LAT data for periodic modulation of the gamma-ray brightness at the 16.35-day period of Radio-Burst activity and detect no significant modulation. We compare these deep limits to the predictions of various fast Radio Burst models, but conclude that similar X-ray constraints on a closer fast Radio Burst source would be needed to strongly constrain theory.

  • a repeating fast Radio Burst source localized to a nearby spiral galaxy
    Nature, 2020
    Co-Authors: B Marcote, K Nimmo, J W T Hessels, S P Tendulkar, C G Bassa, Zsolt Paragi, A Keimpema, M Bhardwaj
    Abstract:

    Fast Radio Bursts (FRBs) are brief, bright, extragalactic Radio flashes1,2. Their physical origin remains unknown, but dozens of possible models have been postulated3. Some FRB sources exhibit repeat Bursts4–7. Although over a hundred FRB sources have been discovered8, only four have been localized and associated with a host galaxy9–12, and just one of these four is known to emit repeating FRBs9. The properties of the host galaxies, and the local environments of FRBs, could provide important clues about their physical origins. The first known repeating FRB, however, was localized to a low-metallicity, irregular dwarf galaxy, and the apparently non-repeating sources were localized to higher-metallicity, massive elliptical or star-forming galaxies, suggesting that perhaps the repeating and apparently non-repeating sources could have distinct physical origins. Here we report the precise localization of a second repeating FRB source6, FRB 180916.J0158+65, to a star-forming region in a nearby (redshift 0.0337 ± 0.0002) massive spiral galaxy, whose properties and proximity distinguish it from all known hosts. The lack of both a comparably luminous persistent Radio counterpart and a high Faraday rotation measure6 further distinguish the local environment of FRB 180916.J0158+65 from that of the single previously localized repeating FRB source, FRB 121102. This suggests that repeating FRBs may have a wide range of luminosities, and originate from diverse host galaxies and local environments. Only one repeating fast Radio Burst has been localized, to an irregular dwarf galaxy; now another is found to come from a star-forming region of a nearby spiral galaxy.

  • a direct localization of a fast Radio Burst and its host
    Nature, 2017
    Co-Authors: S Chatterjee, J W T Hessels, C J Law, Robert Wharton, Sarah Burkespolaor, Geoffrey C Bower, J M Cordes, S P Tendulkar
    Abstract:

    Subarcsecond localization of the repeating fast Radio Burst FRB 121102 shows that its source is co-located with a faint galaxy with a low-luminosity active galactic nucleus, or a previously unknown type of extragalactic source. Shami Chatterjee et al. report the subarcsecond localization of the Arecibo-discovered fast Radio Burst FRB 121102, the only known repeating Burst source, using high-time-resolution Radio interferometric observations that directly image the Bursts. FRBs are Radio flashes of unknown physical nature with durations of milliseconds. Previous observations have lacked the resolution to uniquely identify a host or multi-wavelength counterpart. The localization of FRB 121102 reveals a persistent Radio and optical source that is coincident with the Bursts to within 100 milliarcseconds. The enigmatic persistent source could be a neutron star within its nebula in a distant host galaxy, a low-luminosity active galactic nucleus, or a previously unknown type of extragalactic source. Fast Radio Bursts1,2 are astronomical Radio flashes of unknown physical nature with durations of milliseconds. Their dispersive arrival times suggest an extragalactic origin and imply Radio luminosities that are orders of magnitude larger than those of all known short-duration Radio transients3. So far all fast Radio Bursts have been detected with large single-dish telescopes with arcminute localizations, and attempts to identify their counterparts (source or host galaxy) have relied on the contemporaneous variability of field sources4 or the presence of peculiar field stars5 or galaxies4. These attempts have not resulted in an unambiguous association6,7 with a host or multi-wavelength counterpart. Here we report the subarcsecond localization of the fast Radio Burst FRB 121102, the only known repeating Burst source8,9,10,11, using high-time-resolution Radio interferometric observations that directly image the Bursts. Our precise localization reveals that FRB 121102 originates within 100 milliarcseconds of a faint 180-microJansky persistent Radio source with a continuum spectrum that is consistent with non-thermal emission, and a faint (twenty-fifth magnitude) optical counterpart. The flux density of the persistent Radio source varies by around ten per cent on day timescales, and very long baseline Radio interferometry yields an angular size of less than 1.7 milliarcseconds. Our observations are inconsistent with the fast Radio Burst having a Galactic origin or its source being located within a prominent star-forming galaxy. Instead, the source appears to be co-located with a low-luminosity active galactic nucleus or a previously unknown type of extragalactic source. Localization and identification of a host or counterpart has been essential to understanding the origins and physics of other kinds of transient events, including gamma-ray Bursts12,13 and tidal disruption events14. However, if other fast Radio Bursts have similarly faint Radio and optical counterparts, our findings imply that direct subarcsecond localizations may be the only way to provide reliable associations.

  • A repeating fast Radio Burst
    Nature, 2016
    Co-Authors: Laura Spitler, J W T Hessels, P Scholz, S Chatterjee, J M Cordes, Slavko Bogdanov, Adam Brazier, Fernando Camilo, Fronefield Crawford, J. S. Deneva
    Abstract:

    Observations of repeated fast Radio Bursts, having dispersion measures and sky positions consistent with those of FRB 121102, show that the signals do not originate in a single cataclysmic event and may come from a young, highly magnetized, extragalactic neutron star. Fast Radio Bursts (FRBs) are transient Radio pulses that last a few milliseconds. They are thought to be extragalactic, and are of unknown physical origin. Many FRB models have proposed the cause to be one-time-only cataclysmic events. Follow-up monitoring of detected Bursts did not reveal repeat Bursts, consistent with such models. However, this paper reports ten additional Bursts from the direction of FRB 121102, demonstrating that its source survived the energetic events that caused the Bursts. Although there may be multiple physical origins for the Burst, the repeating Bursts seen from FRB 121102 support an origin in a young, highly magnetized, extragalactic neutron star. Fast Radio Bursts are millisecond-duration astronomical Radio pulses of unknown physical origin that appear to come from extragalactic distances1,2,3,4,5,6,7,8. Previous follow-up observations have failed to find additional Bursts at the same dispersion measure (that is, the integrated column density of free electrons between source and telescope) and sky position as the original detections9. The apparent non-repeating nature of these Bursts has led to the suggestion that they originate in cataclysmic events10. Here we report observations of ten additional Bursts from the direction of the fast Radio Burst FRB 121102. These Bursts have dispersion measures and sky positions consistent with the original Burst4. This unambiguously identifies FRB 121102 as repeating and demonstrates that its source survives the energetic events that cause the Bursts. Additionally, the Bursts from FRB 121102 show a wide range of spectral shapes that appear to be predominantly intrinsic to the source and which vary on timescales of minutes or less. Although there may be multiple physical origins for the population of fast Radio Bursts, these repeat Bursts with high dispersion measure and variable spectra specifically seen from the direction of FRB 121102 support an origin in a young, highly magnetized, extragalactic neutron star11,12.

Kevin Bandura - One of the best experts on this subject based on the ideXlab platform.

  • the first chime frb fast Radio Burst catalog
    arXiv: High Energy Astrophysical Phenomena, 2021
    Co-Authors: M Amiri, M Bhardwaj, B C Andersen, Kevin Bandura, M M Boyce, P J Boyle, C Brar, Sabrina Berger, D Breitman, T Cassanelli
    Abstract:

    We present a catalog of 535 fast Radio Bursts (FRBs) detected by the Canadian Hydrogen Intensity Mapping Experiment Fast Radio Burst (CHIME/FRB) Project between 400 and 800 MHz from 2018 July 25 to 2019 July 1, including 61 Bursts from 18 previously reported repeating sources. The catalog represents the first large sample, including Bursts from repeaters and non-repeaters, observed in a single survey with uniform selection effects. This facilitates comparative and absolute studies of the FRB population. We show that repeaters and apparent non-repeaters have sky locations and dispersion measures (DMs) that are consistent with being drawn from the same distribution. However, Bursts from repeating sources differ from apparent non-repeaters in intrinsic temporal width and spectral bandwidth. Through injection of simulated events into our detection pipeline, we perform an absolute calibration of selection effects to account for systematic biases. We find evidence for a population of FRBs - comprising a large fraction of the overall population - with a scattering time at 600 MHz in excess of 10 ms, of which only a small fraction are observed by CHIME/FRB. We infer a power-law index for the cumulative fluence distribution of $\alpha=-1.40\pm0.11(\textrm{stat.})^{+0.060}_{-0.085}(\textrm{sys.})$, consistent with the $-3/2$ expectation for a non-evolving population in Euclidean space. We find $\alpha$ is steeper for high-DM events and shallower for low-DM events, which is what would be expected when DM is correlated with distance. We infer a sky rate of $[818\pm64(\textrm{stat.})^{+220}_{-200}({\textrm{sys.}})]/\textrm{sky}/\textrm{day}$ above a fluence of 5 Jy ms at 600 MHz, with scattering time at $600$ MHz under 10 ms, and DM above 100 pc cm$^{-3}$.

  • a bright millisecond duration Radio Burst from a galactic magnetar
    Nature, 2020
    Co-Authors: B C Andersen, M Bhardwaj, Kevin Bandura, M M Boyce, P J Boyle, C Brar, T Cassanelli, P Chawla, A Bij, T Chen
    Abstract:

    Magnetars are highly magnetized young neutron stars that occasionally produce enormous Bursts and flares of X-rays and gamma-rays. Of the approximately thirty magnetars currently known in our Galaxy and Magellanic Clouds, five have exhibited transient Radio pulsations. Fast Radio Bursts (FRBs) are millisecond-duration Bursts of Radio waves arriving from cosmological distances. Some have been seen to repeat. A leading model for repeating FRBs is that they are extragalactic magnetars, powered by their intense magnetic fields. However, a challenge to this model has been that FRBs must have Radio luminosities many orders of magnitude larger than those seen from known Galactic magnetars. Here we report the detection of an extremely intense Radio Burst from the Galactic magnetar SGR 1935+2154 using the Canadian Hydrogen Intensity Mapping Experiment (CHIME) FRB project. The fluence of this two-component bright Radio Burst and the estimated distance to SGR 1935+2154 together imply a 400-800 MHz Burst energy of $\sim 3 \times 10^{34}$ erg, which is three orders of magnitude brighter than those of any Radio-emitting magnetar detected thus far. Such a Burst coming from a nearby galaxy would be indistinguishable from a typical FRB. This event thus bridges a large fraction of the Radio energy gap between the population of Galactic magnetars and FRBs, strongly supporting the notion that magnetars are the origin of at least some FRBs.

  • simultaneous x ray and Radio observations of the repeating fast Radio Burst frb 180916 j0158 65
    The Astrophysical Journal, 2020
    Co-Authors: P Scholz, J W T Hessels, L G Spitler, A Cook, Marilyn Cruces, V M Kaspi, Walid A Majid, A Naidu, Aaron B Pearlman, Kevin Bandura
    Abstract:

    We report on simultaneous Radio and X-ray observations of the repeating fast Radio Burst source FRB 180916.J0158+65 using the Canadian Hydrogen Intensity Mapping Experiment (CHIME), Effelsberg, and Deep Space Network (DSS-14 and DSS-63) Radio telescopes and the Chandra X-ray Observatory. During 33 ks of Chandra observations, we detect no Radio Bursts in overlapping Effelsberg or Deep Space Network observations and a single Burst during CHIME/FRB source transits. We detect no X-ray events in excess of the background during the Chandra observations. These non-detections imply a 5 sigma limit of <5 x 10(-10)erg cm(-2)for the 0.5-10 keV fluence of prompt emission at the time of the Radio Burst and 1.3 x 10(-9)erg cm(-2)at any time during the Chandra observations. Given the host-galaxy redshift of FRB 180916.J0158+65 (z similar to 0.034), these correspond to energy limits of <1.6 x 10(45)erg and <4 x 10(45)erg, respectively. We also place a 5 sigma limit of <8 x 10(-15)erg s(-1) cm(-2)on the 0.5-10 keV absorbed flux of a persistent source at the location of FRB 180916.J0158+65. This corresponds to a luminosity limit of <2 x 10(40)erg s(-1). Using an archival set of Radio Bursts from FRB 180916.J0158+65, we search for prompt gamma-ray emission in Fermi/GBM data but find no significant gamma-ray Bursts, thereby placing a limit of 9 x 10(-9)erg cm(-2)on the 10-100 keV fluence. We also search Fermi/LAT data for periodic modulation of the gamma-ray brightness at the 16.35 days period of Radio Burst activity and detect no significant modulation. We compare these deep limits to the predictions of various fast Radio Burst models, but conclude that similar X-ray constraints on a closer fast Radio Burst source would be needed to strongly constrain theory.

  • simultaneous x ray and Radio observations of the repeating fast Radio Burst frb 180916 j0158 65
    arXiv: High Energy Astrophysical Phenomena, 2020
    Co-Authors: P Scholz, J W T Hessels, L G Spitler, A Cook, Marilyn Cruces, V M Kaspi, Walid A Majid, A Naidu, Aaron B Pearlman, Kevin Bandura
    Abstract:

    We report on simultaneous Radio and X-ray observations of the repeating fast Radio Burst source FRB 180916.J0158+65 using the Canadian Hydrogen Intensity Mapping Experiment (CHIME), Effelsberg, and Deep Space Network (DSS-14 and DSS-63) Radio telescopes and the Chandra X-ray Observatory. During 33 ks of Chandra observations, we detect no Radio Bursts in overlapping Effelsberg or Deep Space Network observations and a single Radio Burst during CHIME/FRB source transits. We detect no X-ray events in excess of the background during the Chandra observations. These non-detections imply a 5-$\sigma$ limit of $<5\times10^{-10}$ erg cm$^{-2}$ for the 0.5--10 keV fluence of prompt emission at the time of the Radio Burst and $1.3\times10^{-9}$ erg cm$^{-2}$ at any time during the Chandra observations at the position of FRB 180916.J0158+65. Given the host-galaxy redshift of FRB 180916.J0158+65 ($z\sim0.034$), these correspond to energy limits of $<1.6\times10^{45}$ erg and $<4\times10^{45}$ erg, respectively. We also place a 5-$\sigma$ limit of $<8\times10^{-15}$ erg s$^{-1}$ cm$^{-2}$ on the 0.5--10\,keV absorbed flux of a persistent source at the location of FRB 180916.J0158+65. This corresponds to a luminosity limit of $<2\times10^{40}$ erg s$^{-1}$. Using Fermi/GBM data we search for prompt gamma-ray emission at the time of Radio Bursts from FRB 180916.J0158+65 and find no significant Bursts, placing a limit of $4\times10^{-9}$ erg cm$^{-2}$ on the 10--100 keV fluence. We also search Fermi/LAT data for periodic modulation of the gamma-ray brightness at the 16.35-day period of Radio-Burst activity and detect no significant modulation. We compare these deep limits to the predictions of various fast Radio Burst models, but conclude that similar X-ray constraints on a closer fast Radio Burst source would be needed to strongly constrain theory.

  • chime frb detection of the original repeating fast Radio Burst source frb 121102
    The Astrophysical Journal, 2019
    Co-Authors: A Josephy, M Bhardwaj, B C Andersen, Kevin Bandura, P Chawla, P Scholz, E Fonseca, C Patel, Z Pleunis, M M Boyce
    Abstract:

    We report the detection of a single Burst from the first-discovered repeating Fast Radio Burst source, FRB 121102, with CHIME/FRB, which operates in the frequency band 400-800 MHz. The detected Burst occurred on 2018 November 19 and its emission extends down to at least 600 MHz, the lowest frequency detection of this source yet. The Burst, detected with a significance of 23.7$\sigma$, has fluence 12$\pm$3 Jy ms and shows complex time and frequency morphology. The 34 ms width of the Burst is the largest seen for this object at any frequency. We find evidence of sub-Burst structure that drifts downward in frequency at a rate of -3.9$\pm$0.2 MHz ms$^{-1}$. Our best fit tentatively suggests a dispersion measure of 563.6$\pm$0.5 pc cm$^{-3}$, which is ${\approx}$1% higher than previously measured values. We set an upper limit on the scattering time at 500 MHz of 9.6 ms, which is consistent with expectations from the extrapolation from higher frequency data. We have exposure to the position of FRB 121102 for a total of 11.3 hrs within the FWHM of the synthesized beams at 600 MHz from 2018 July 25 to 2019 February 25. We estimate on the basis of this single event an average Burst rate for FRB 121102 of 0.1-10 per day in the 400-800 MHz band for a median fluence threshold of 7 Jy ms in the stated time interval.

M Bhardwaj - One of the best experts on this subject based on the ideXlab platform.

  • the first chime frb fast Radio Burst catalog
    arXiv: High Energy Astrophysical Phenomena, 2021
    Co-Authors: M Amiri, M Bhardwaj, B C Andersen, Kevin Bandura, M M Boyce, P J Boyle, C Brar, Sabrina Berger, D Breitman, T Cassanelli
    Abstract:

    We present a catalog of 535 fast Radio Bursts (FRBs) detected by the Canadian Hydrogen Intensity Mapping Experiment Fast Radio Burst (CHIME/FRB) Project between 400 and 800 MHz from 2018 July 25 to 2019 July 1, including 61 Bursts from 18 previously reported repeating sources. The catalog represents the first large sample, including Bursts from repeaters and non-repeaters, observed in a single survey with uniform selection effects. This facilitates comparative and absolute studies of the FRB population. We show that repeaters and apparent non-repeaters have sky locations and dispersion measures (DMs) that are consistent with being drawn from the same distribution. However, Bursts from repeating sources differ from apparent non-repeaters in intrinsic temporal width and spectral bandwidth. Through injection of simulated events into our detection pipeline, we perform an absolute calibration of selection effects to account for systematic biases. We find evidence for a population of FRBs - comprising a large fraction of the overall population - with a scattering time at 600 MHz in excess of 10 ms, of which only a small fraction are observed by CHIME/FRB. We infer a power-law index for the cumulative fluence distribution of $\alpha=-1.40\pm0.11(\textrm{stat.})^{+0.060}_{-0.085}(\textrm{sys.})$, consistent with the $-3/2$ expectation for a non-evolving population in Euclidean space. We find $\alpha$ is steeper for high-DM events and shallower for low-DM events, which is what would be expected when DM is correlated with distance. We infer a sky rate of $[818\pm64(\textrm{stat.})^{+220}_{-200}({\textrm{sys.}})]/\textrm{sky}/\textrm{day}$ above a fluence of 5 Jy ms at 600 MHz, with scattering time at $600$ MHz under 10 ms, and DM above 100 pc cm$^{-3}$.

  • a bright fast Radio Burst from frb 20200120e with sub 100 nanosecond structure
    arXiv: High Energy Astrophysical Phenomena, 2021
    Co-Authors: Walid A Majid, M Bhardwaj, T Cassanelli, Aaron B Pearlman, Robert Wharton, Thomas A Prince, C J Naudet, Karishma Bansal, Calvin Leung, B W Meyers
    Abstract:

    We present the detection of a bright Radio Burst at Radio frequencies between 2.2--2.3 GHz with the NASA Deep Space Network (DSN) 70 m dish (DSS-63) in Madrid, Spain from FRB~20200120E. This repeating fast Radio Burst (FRB) was recently discovered by the Canadian Hydrogen Intensity Mapping Experiment Fast Radio Burst (CHIME/FRB) instrument and reported to be associated with the M81 spiral galaxy at a distance of 3.6 Mpc. The high time resolution capabilities of the recording system used in this observation, together with the small amount of scattering and intrinsic brightness of the Burst, allow us to explore the Burst structure in unprecedented detail. We find that the Burst has a duration of roughly 30 $\mu$s and is comprised of several narrow components with typical separations of 2--3 $\mu$s. The narrowest component has a width of $\lesssim$ 100 ns, which corresponds to a light travel time size as small as 30 m, the smallest associated with an FRB to date. The peak flux density of the narrowest Burst component is 270 Jy. We estimate the total spectral luminosity of the narrowest component of the Burst to be 4 $\times$ 10$^{\text{30}}$ erg s$^{\text{-1}}$ Hz$^{\text{-1}}$, which is a factor of $\sim$500 above the luminosities of the so-called "nanoshots" associated with giant pulses from the Crab pulsar. This spectral luminosity is also higher than that of the Radio Bursts detected from the Galactic magnetar SGR 1935+2154 during its outBurst in April 2020, but it falls on the low-end of the currently measured luminosity distribution of extragalatic FRBs. These results provide further support for the presence of a continuum of FRB Burst luminosities.

  • a bright millisecond duration Radio Burst from a galactic magnetar
    Nature, 2020
    Co-Authors: B C Andersen, M Bhardwaj, Kevin Bandura, M M Boyce, P J Boyle, C Brar, T Cassanelli, P Chawla, A Bij, T Chen
    Abstract:

    Magnetars are highly magnetized young neutron stars that occasionally produce enormous Bursts and flares of X-rays and gamma-rays. Of the approximately thirty magnetars currently known in our Galaxy and Magellanic Clouds, five have exhibited transient Radio pulsations. Fast Radio Bursts (FRBs) are millisecond-duration Bursts of Radio waves arriving from cosmological distances. Some have been seen to repeat. A leading model for repeating FRBs is that they are extragalactic magnetars, powered by their intense magnetic fields. However, a challenge to this model has been that FRBs must have Radio luminosities many orders of magnitude larger than those seen from known Galactic magnetars. Here we report the detection of an extremely intense Radio Burst from the Galactic magnetar SGR 1935+2154 using the Canadian Hydrogen Intensity Mapping Experiment (CHIME) FRB project. The fluence of this two-component bright Radio Burst and the estimated distance to SGR 1935+2154 together imply a 400-800 MHz Burst energy of $\sim 3 \times 10^{34}$ erg, which is three orders of magnitude brighter than those of any Radio-emitting magnetar detected thus far. Such a Burst coming from a nearby galaxy would be indistinguishable from a typical FRB. This event thus bridges a large fraction of the Radio energy gap between the population of Galactic magnetars and FRBs, strongly supporting the notion that magnetars are the origin of at least some FRBs.

  • nine new repeating fast Radio Burst sources from chime frb
    The Astrophysical Journal, 2020
    Co-Authors: E Fonseca, M Bhardwaj, B C Andersen, P Chawla, V M Kaspi, D C Good, A Josephy, Kiyoshi Masui, R Mckinven, D Michilli
    Abstract:

    We report on the discovery and analysis of Bursts from nine new repeating fast Radio Burst (FRB) sources found using the Canadian Hydrogen Intensity Mapping Experiment (CHIME) telescope. These sources span a dispersion measure (DM) range of 195 to 1380 pc cm$^{-3}$. We detect two Bursts from three of the new sources, three Bursts from four of the new sources, four Bursts from one new source, and five Bursts from one new source. We determine sky coordinates of all sources with uncertainties of $\sim$10$^\prime$. We detect Faraday rotation measures for two sources, with values $-20(1)$ and $-499.8(7)$ rad m$^{-2}$, that are substantially lower than the RM derived from Bursts emitted by FRB 121102. We find that the DM distribution of our events, combined with the nine other repeaters discovered by CHIME/FRB, is indistinguishable from that of thus far non-repeating CHIME/FRB events. However, as previously reported, the Burst widths appear statistically significantly larger than the thus far non-repeating CHIME/FRB events, further supporting the notion of inherently different emission mechanisms and/or local environments. These results are consistent with previous work, though are now derived from 18 repeating sources discovered by CHIME/FRB during its first year of operation. We identify candidate galaxies that may contain FRB 190303.J1353+48 (DM = 222.4 pc cm$^{-3}$).

  • nine new repeating fast Radio Burst sources from chime frb
    The Astrophysical Journal, 2020
    Co-Authors: E Fonseca, M Bhardwaj, B C Andersen, P Chawla, V M Kaspi, D C Good, A Josephy, Kiyoshi Masui, R Mckinven, D Michilli
    Abstract:

    We report on the discovery and analysis of Bursts from nine new repeating fast Radio Burst (FRB) sources found using the Canadian Hydrogen Intensity Mapping Experiment (CHIME) telescope. These sources span a dispersion measure (DM) range of 195–1380 pc cm−3. We detect two Bursts from three of the new sources, three Bursts from four of the new sources, four Bursts from one new source, and five Bursts from one new source. We determine sky coordinates of all sources with uncertainties of ∼10′. We detect Faraday rotation measures (RMs) for two sources, with values −20(1) and −499.8(7) rad m−2, that are substantially lower than the RM derived from Bursts emitted by FRB 121102. We find that the DM distribution of our events, combined with the nine other repeaters discovered by CHIME/FRB, is indistinguishable from that of thus far non-repeating CHIME/FRB events. However, as previously reported, the Burst widths appear statistically significantly larger than the thus far non-repeating CHIME/FRB events, further supporting the notion of inherently different emission mechanisms and/or local environments. These results are consistent with previous work, though are now derived from 18 repeating sources discovered by CHIME/FRB during its first year of operation. We identify candidate galaxies that may contain FRB 190303.J1353+48 (DM = 222.4 pc cm−3).

Shiwei Feng - One of the best experts on this subject based on the ideXlab platform.

  • a solar stationary type iv Radio Burst and its radiation mechanism
    Solar Physics, 2018
    Co-Authors: Kyung-suk Cho, V Vasanth, Shiwei Feng, Yao Chen, Hongyu Liu, A A Koval
    Abstract:

    A stationary Type IV (IVs) Radio Burst was observed on September 24, 2011. Observations from the Nancay RadioHeliograph (NRH) show that the brightness temperature (\(T_{\mathrm{B}}\)) of this Burst is extremely high, over \(10^{11}\) K at 150 MHz and over \(10^{8}\) K in general. The degree of circular polarization (\(q\)) is between \(-60\% \sim -100\%\), which means that it is highly left-handed circularly polarized. The flux–frequency spectrum follows a power-law distribution, and the spectral index is considered to be roughly \(-3 \sim -4\) throughout the IVs. Radio sources of this event are located in the wake of the coronal mass ejection and are spatially dispersed. They line up to present a formation in which lower-frequency sources are higher. Based on these observations, it is suggested that the IVs was generated through electron cyclotron maser emission.

  • observation of a metric type n solar Radio Burst
    arXiv: Solar and Stellar Astrophysics, 2016
    Co-Authors: Xiangliang Kong, V Vasanth, Shiwei Feng, Yao Chen, A A Koval, Bing Wang, Fan Guo
    Abstract:

    Type III and type-III-like Radio Bursts are produced by energetic electron beams guided along coronal magnetic fields. As a variant of type III Bursts, Type N Bursts appear as the letter "N" in the Radio dynamic spectrum and reveal a magnetic mirror effect in coronal loops. Here, we report a well-observed N-shaped Burst consisting of three successive branches at metric wavelength with both fundamental and harmonic components and a high brightness temperature ($>$10$^9$ K). We verify the Burst as a true type N Burst generated by the same electron beam from three aspects of the data. First, durations of the three branches at a given frequency increase gradually, may due to the dispersion of the beam along its path. Second, the flare site, as the only possible source of non-thermal electrons, is near the western feet of large-scale closed loops. Third, the first branch and the following two branches are localized at different legs of the loops with opposite sense of polarization. We also find that the sense of polarization of the Radio Burst is in contradiction to the O-mode and there exists a fairly large time delay ($\sim$3-5 s) between the fundamental and harmonic components. Possible explanations accounting for these observations are presented. Assuming the classical plasma emission mechanism, we can infer coronal parameters such as electron density and magnetic field near the Radio source and make diagnostics on the magnetic mirror process.

  • a solar type ii Radio Burst from coronal mass ejection coronal ray interaction simultaneous Radio and extreme ultraviolet imaging
    The Astrophysical Journal, 2014
    Co-Authors: Yao Chen, Shiwei Feng, Xiangliang Kong, Fan Guo, Li Feng, Bing Wang
    Abstract:

    Simultaneous Radio and extreme ultraviolet (EUV)/white-light imaging data are examined for a solar type II Radio Burst occurring on 2010 March 18 to deduce its source location. Using a bow-shock model, we reconstruct the three-dimensional EUV wave front (presumably the type-II-emitting shock) based on the imaging data of the two Solar TErrestrial RElations Observatory spacecraft. It is then combined with the Nancay Radio imaging data to infer the three-dimensional position of the type II source. It is found that the type II source coincides with the interface between the coronal mass ejection (CME) EUV wave front and a nearby coronal ray structure, providing evidence that the type II emission is physically related to the CME-ray interaction. This result, consistent with those of previous studies, is based on simultaneous Radio and EUV imaging data for the first time.

  • a solar type ii Radio Burst from cme coronal ray interaction simultaneous Radio and euv imaging
    arXiv: Space Physics, 2014
    Co-Authors: Yao Chen, Shiwei Feng, Xiangliang Kong, Fan Guo, Li Feng, Bing Wang
    Abstract:

    Simultaneous Radio and extreme ultraviolet (EUV)/white-light imaging data are examined for a solar type II Radio Burst occurring on 2010 March 18 to deduce its source location. Using a bow-shock model, we reconstruct the 3-dimensional EUV wave front (presumably the type-II emitting shock) based on the imaging data of the two STEREO spacecraft. It is then combined with the Nan\c{c}ay Radio imaging data to infer the 3-dimensional position of the type II source. It is found that the type II source coincides with the interface between the CME EUV wave front and a nearby coronal ray structure, providing evidence that the type II emission is physically related to the CME-ray interaction. This result, consistent with those of previous studies, is based on simultaneous Radio and EUV imaging data for the first time.

  • Radio signatures of coronal mass ejection streamer interaction and source diagnostics of type ii Radio Burst
    The Astrophysical Journal, 2012
    Co-Authors: Shiwei Feng, Xiangliang Kong, Yao Chen, Hongqiang Song, Xueshang Feng, Ying Liu
    Abstract:

    It has been suggested that type II Radio Bursts are due to energetic electrons accelerated at coronal shocks. Radio observations, however, have poor or no spatial resolutions to pinpoint the exact acceleration locations of these electrons. In this paper, we discuss a promising approach to infer the electron acceleration location by combining Radio and white light observations. The key assumption is to relate specific morphological features (e.g., spectral bumps) of the dynamic spectra of type II Radio Bursts to imaging features (e.g., coronal mass ejection (CME) going into a streamer) along the CME (and its driven shock) propagation. In this study, we examine the CME-streamer interaction for the solar eruption dated on 2003 November 1. The presence of spectral bump in the relevant type II Radio Burst is identified, which is interpreted as a natural result of the shock-Radio-emitting region entering the dense streamer structure. The study is useful for further determinations of the location of type II Radio Burst and the associated electron acceleration by CME-driven shock.

L G Spitler - One of the best experts on this subject based on the ideXlab platform.

  • rotation measure evolution of the repeating fast Radio Burst source frb 121102
    The Astrophysical Journal, 2021
    Co-Authors: G H Hilmarsson, L G Spitler, Robert Wharton, D Michilli, Paul Demorest, G Desvignes, K Gourdji, S Hackstein, J W T Hessels
    Abstract:

    The repeating fast Radio Burst source FRB 121102 has been shown to have an exceptionally high and variable Faraday rotation measure (RM), which must be imparted within its host galaxy and likely by or within its local environment. In the redshifted ($z=0.193$) source reference frame, the RM decreased from $1.46\times10^5$~rad~m$^{-2}$ to $1.33\times10^5$~rad~m$^{-2}$ between January and August 2017, showing day-timescale variations of $\sim200$~rad~m$^{-2}$. Here we present sixteen FRB 121102 RMs from Burst detections with the Arecibo 305-m Radio telescope, the Effelsberg 100-m, and the Karl G. Jansky Very Large Array, providing a record of FRB 121102's RM over a 2.5-year timespan. Our observations show a decreasing trend in RM, although the trend is not linear, dropping by an average of 15\% year$^{-1}$ and is $\sim9.7\times10^4$~rad~m$^{-2}$ at the most recent epoch of August 2019. Erratic, short-term RM variations of $\sim10^3$~rad~m$^{-2}$ week$^{-1}$ were also observed between MJDs 58215--58247. A decades-old neutron star embedded within a still-compact supernova remnant or a neutron star near a massive black hole and its accretion torus have been proposed to explain the high RMs. We compare the observed RMs to theoretical models describing the RM evolution for FRBs originating within a supernova remnant. FRB 121102's age is unknown, and we find that the models agree for source ages of $\sim6-17$~years at the time of the first available RM measurements in 2017. We also draw comparisons to the decreasing RM of the Galactic center magnetar, PSR J1745--2900.

  • simultaneous x ray and Radio observations of the repeating fast Radio Burst frb 180916 j0158 65
    The Astrophysical Journal, 2020
    Co-Authors: P Scholz, J W T Hessels, L G Spitler, A Cook, Marilyn Cruces, V M Kaspi, Walid A Majid, A Naidu, Aaron B Pearlman, Kevin Bandura
    Abstract:

    We report on simultaneous Radio and X-ray observations of the repeating fast Radio Burst source FRB 180916.J0158+65 using the Canadian Hydrogen Intensity Mapping Experiment (CHIME), Effelsberg, and Deep Space Network (DSS-14 and DSS-63) Radio telescopes and the Chandra X-ray Observatory. During 33 ks of Chandra observations, we detect no Radio Bursts in overlapping Effelsberg or Deep Space Network observations and a single Burst during CHIME/FRB source transits. We detect no X-ray events in excess of the background during the Chandra observations. These non-detections imply a 5 sigma limit of <5 x 10(-10)erg cm(-2)for the 0.5-10 keV fluence of prompt emission at the time of the Radio Burst and 1.3 x 10(-9)erg cm(-2)at any time during the Chandra observations. Given the host-galaxy redshift of FRB 180916.J0158+65 (z similar to 0.034), these correspond to energy limits of <1.6 x 10(45)erg and <4 x 10(45)erg, respectively. We also place a 5 sigma limit of <8 x 10(-15)erg s(-1) cm(-2)on the 0.5-10 keV absorbed flux of a persistent source at the location of FRB 180916.J0158+65. This corresponds to a luminosity limit of <2 x 10(40)erg s(-1). Using an archival set of Radio Bursts from FRB 180916.J0158+65, we search for prompt gamma-ray emission in Fermi/GBM data but find no significant gamma-ray Bursts, thereby placing a limit of 9 x 10(-9)erg cm(-2)on the 10-100 keV fluence. We also search Fermi/LAT data for periodic modulation of the gamma-ray brightness at the 16.35 days period of Radio Burst activity and detect no significant modulation. We compare these deep limits to the predictions of various fast Radio Burst models, but conclude that similar X-ray constraints on a closer fast Radio Burst source would be needed to strongly constrain theory.

  • a fast Radio Burst discovered in fast drift scan survey
    The Astrophysical Journal, 2020
    Co-Authors: Bing Zhang, L G Spitler, M Kramer, Rui Luo, W W Zhu, Chenchen Miao, D R Lorimer, D J Champion, Youling Yue
    Abstract:

    We report the discovery of a highly dispersed fast Radio Burst (FRB), FRB 181123, from an analysis of ∼1500 hr of drift scan survey data taken using the Five-hundred-meter Aperture Spherical Radio Telescope (FAST). The pulse has three distinct emission components, which vary with frequency across our 1.0–1.5 GHz observing band. We measure the peak flux density to be >0.065 Jy and the corresponding fluence >0.2 Jy ms. Based on the observed dispersion measure of 1812 cm−3 pc, we infer a redshift of ∼1.9. From this, we estimate the peak luminosity and isotropic energy to be ≲2 × 1043 erg s−1 and ≲2 × 1040 erg, respectively. With only one FRB from the survey detected so far, our constraints on the event rate are limited. We derive a 95% confidence lower limit for the event rate of 900 FRBs per day for FRBs with fluences >0.025 Jy ms. We performed follow-up observations of the source with FAST for four hours and have not found a repeated Burst. We discuss the implications of this discovery for our understanding of the physical mechanisms of FRBs.

  • a fast Radio Burst discovered in fast drift scan survey
    arXiv: High Energy Astrophysical Phenomena, 2020
    Co-Authors: Bing Zhang, L G Spitler, M Kramer, Rui Luo, W W Zhu, Chenchen Miao, D R Lorimer, D J Champion, Youling Yue
    Abstract:

    We report the discovery of a highly dispersed fast Radio Burst, FRB~181123, from an analysis of $\sim$1500~hr of drift-scan survey data taken using the Five-hundred-meter Aperture Spherical Radio Telescope (FAST). The pulse has three distinct emission components, which vary with frequency across our 1.0--1.5~GHz observing band. We measure the peak flux density to be $>0.065$~Jy and the corresponding fluence $>0.2$~Jy~ms. Based on the observed dispersion measure of 1812~cm$^{-3}$~pc, we infer a redshift of $\sim 1.9$. From this, we estimate the peak luminosity and isotropic energy to be $\lesssim 2\times10^{43}$~erg~s$^{-1}$ and $\lesssim 2\times10^{40}$~erg, respectively. With only one FRB from the survey detected so far, our constraints on the event rate are limited. We derive a 95\% confidence lower limit for the event rate of 900 FRBs per day for FRBs with fluences $>0.025$~Jy~ms. We performed follow-up observations of the source with FAST for four hours and have not found a repeated Burst. We discuss the implications of this discovery for our understanding of the physical mechanisms of FRBs.

  • simultaneous x ray and Radio observations of the repeating fast Radio Burst frb 180916 j0158 65
    arXiv: High Energy Astrophysical Phenomena, 2020
    Co-Authors: P Scholz, J W T Hessels, L G Spitler, A Cook, Marilyn Cruces, V M Kaspi, Walid A Majid, A Naidu, Aaron B Pearlman, Kevin Bandura
    Abstract:

    We report on simultaneous Radio and X-ray observations of the repeating fast Radio Burst source FRB 180916.J0158+65 using the Canadian Hydrogen Intensity Mapping Experiment (CHIME), Effelsberg, and Deep Space Network (DSS-14 and DSS-63) Radio telescopes and the Chandra X-ray Observatory. During 33 ks of Chandra observations, we detect no Radio Bursts in overlapping Effelsberg or Deep Space Network observations and a single Radio Burst during CHIME/FRB source transits. We detect no X-ray events in excess of the background during the Chandra observations. These non-detections imply a 5-$\sigma$ limit of $<5\times10^{-10}$ erg cm$^{-2}$ for the 0.5--10 keV fluence of prompt emission at the time of the Radio Burst and $1.3\times10^{-9}$ erg cm$^{-2}$ at any time during the Chandra observations at the position of FRB 180916.J0158+65. Given the host-galaxy redshift of FRB 180916.J0158+65 ($z\sim0.034$), these correspond to energy limits of $<1.6\times10^{45}$ erg and $<4\times10^{45}$ erg, respectively. We also place a 5-$\sigma$ limit of $<8\times10^{-15}$ erg s$^{-1}$ cm$^{-2}$ on the 0.5--10\,keV absorbed flux of a persistent source at the location of FRB 180916.J0158+65. This corresponds to a luminosity limit of $<2\times10^{40}$ erg s$^{-1}$. Using Fermi/GBM data we search for prompt gamma-ray emission at the time of Radio Bursts from FRB 180916.J0158+65 and find no significant Bursts, placing a limit of $4\times10^{-9}$ erg cm$^{-2}$ on the 10--100 keV fluence. We also search Fermi/LAT data for periodic modulation of the gamma-ray brightness at the 16.35-day period of Radio-Burst activity and detect no significant modulation. We compare these deep limits to the predictions of various fast Radio Burst models, but conclude that similar X-ray constraints on a closer fast Radio Burst source would be needed to strongly constrain theory.