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Jeremy P Scott - One of the best experts on this subject based on the ideXlab platform.
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The Herschel SPIRE Fourier Transform Spectrometer Spectral Feature Finder – V. Rotational measurements of NGC 891
Monthly Notices of the Royal Astronomical Society, 2020Co-Authors: Chris S Benson, Jeremy P Scott, I Valtchanov, Locke D. Spencer, N HladczukAbstract:ABSTRACT The ESA Herschel Spectral and Photometric Imaging Receiver (SPIRE) Fourier Transform Spectrometer (FTS) Spectral Feature Finder (FF) project is an automated Spectral Feature fitting routine developed within the SPIRE instrument team to extract all prominent Spectral Features from all publicly available SPIRE FTS observations. In this work, we demonstrate the use of the FF information extracted from three observations of the edge-on spiral galaxy NGC 891 to measure the rotation of N ii and C i gas at far-infrared frequencies in complement to radio observations of the [H i] 21-cm line and the CO(1-0) transition as well as optical measurements of Hα. We find that measurements of both N ii and C i gas follow a similar velocity profile to that of H i and Hα showing a correlation between neutral and ionized regions of the interstellar medium in the disc of NGC 891.
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the herschel spire fourier transform spectrometer Spectral Feature finder v rotational measurements of ngc 891
arXiv: Astrophysics of Galaxies, 2020Co-Authors: Chris S Benson, L D Spencer, Jeremy P Scott, I Valtchanov, N HladczukAbstract:The ESA Herschel Spectral and Photometric Imaging Receiver (SPIRE) Fourier Transform Spectrometer (FTS) Spectral Feature Finder (FF) project is an automated Spectral Feature fitting routine developed within the SPIRE instrument team to extract all prominent Spectral Features from all publicly available SPIRE FTS observations. In this work, we demonstrate the use of the FF information extracted from three observations of the edge-on spiral galaxy NGC 891 to measure the rotation of NII and CI gas at Far-infrared frequencies in complement to radio observations of the HI 21cm line and the CO(1-0) transition as well as optical measurements of Halpha. We find that measurements of both NII and CI gas follow a similar velocity profile to that of HI and Halpha showing a correlation between neutral and ionized regions of the interstellar medium (ISM) in the disk of NGC 891.
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the herschel spire fourier transform spectrometer Spectral Feature finder iii line identification and off axis spectra
Monthly Notices of the Royal Astronomical Society, 2020Co-Authors: Chris S Benson, N Hladczuk, L D Spencer, A Robb, Jeremy P Scott, I Valtchanov, R Hopwood, D A NaylorAbstract:The ESA Herschel Spectral and Photometric Imaging Receiver (SPIRE) Fourier Transform Spectrometer (FTS) Spectral Feature Finder (FF) project is an automated Spectral Feature fitting routine developed within the SPIRE instrument team to extract all prominent Spectral Features from all publicly available SPIRE FTS observations. We present the extension of the FF to include the off-axis detectors of the FTS in sparsely sampled single-pointing observations, the results of which have been ingested into the catalogue. We also present the results from an automated routine for identifications of the atomic/molecular transitions that correspond to the Spectral Features extracted by the FF. We use a template of 307 atomic fine structure and molecular lines that are commonly found in SPIRE FTS spectra for the cross-match. The routine makes use of information provided by the line identification to search for low signal-to-noise ratio Features that have been excluded or missed by the iterative FF. In total, the atomic/molecular transitions of 178,942 lines are identified (corresponding to 83% of the entire FF catalogue), and an additional 33,840 Spectral lines associated with missing Features from SPIRE FTS observations are added to the FF catalogue.
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the herschel spire fourier transform spectrometer Spectral Feature finder iv neutral carbon detection in the spire fts spectra
Monthly Notices of the Royal Astronomical Society, 2020Co-Authors: Jeremy P Scott, L D Spencer, I Valtchanov, R Hopwood, D A NaylorAbstract:The SPIRE FTS Spectral Feature Finder (FF), developed within the Herschel Spectral and Photometric Imaging Receiver (SPIRE) Fourier Transform Spectrometer (FTS) instrument team, is an automated Spectral Feature fitting routine that attempts to find significant Features in SPIRE FTS spectra. The $^3$P$_1$ - $^3$P$_0$ and $^3$P$_2$ - $^3$P$_1$ neutral carbon fine structure lines are common Features in carbon rich far-infrared astrophysical sources. These Features can be difficult to detect using an automated Feature detection routine due to their typically low amplitude and line blending. In this paper we describe and validate the FF sub-routine designed to detect the neutral carbon emission observed in SPIRE Spectral data.
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the herschel spire fourier transform spectrometer Spectral Feature finder i the Spectral Feature finder and catalogue
Monthly Notices of the Royal Astronomical Society, 2020Co-Authors: Chris S Benson, N Hladczuk, L D Spencer, Jeremy P Scott, I Valtchanov, R Hopwood, N Marchili, E T PolehamptonAbstract:We provide a detailed description of the Herschel-SPIRE Fourier Transform Spectrometer (FTS) Spectral Feature Finder (FF). The FF is an automated process designed to extract significant Spectral Features from SPIRE FTS data products. Optimising the number of Features found in SPIRE-FTS spectra is challenging. The wide SPIRE-FTS frequency range (447-1568 GHz) leads to many molecular species and atomic fine structure lines falling within the observed bands. As the best Spectral resolution of the SPIRE-FTS is ~1.2 GHz, there can be significant line blending, depending on the source type. In order to find, both efficiently and reliably, Features in spectra associated with a wide range of sources, the FF iteratively searches for peaks over a number of signal-to-noise ratio (SNR) thresholds. For each threshold, newly identified Features are rigorously checked before being added to the fitting model. At the end of each iteration, the FF simultaneously fits the continuum and Features found, with the resulting residual spectrum used in the next iteration. The final FF products report the frequency of the Features found and the associated SNRs. Line flux determination is not included as part of the FF products, as extracting reliable line flux from SPIRE-FTS data is a complex process that requires careful evaluation and analysis of the spectra on a case-by-case basis. The FF results are 100% complete for Features with SNR greater than 10 and 50-70% complete at SNR of 5. The FF code and all FF products are publicly available via the Herschel Science Archive.
I Valtchanov - One of the best experts on this subject based on the ideXlab platform.
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The Herschel SPIRE Fourier Transform Spectrometer Spectral Feature Finder – V. Rotational measurements of NGC 891
Monthly Notices of the Royal Astronomical Society, 2020Co-Authors: Chris S Benson, Jeremy P Scott, I Valtchanov, Locke D. Spencer, N HladczukAbstract:ABSTRACT The ESA Herschel Spectral and Photometric Imaging Receiver (SPIRE) Fourier Transform Spectrometer (FTS) Spectral Feature Finder (FF) project is an automated Spectral Feature fitting routine developed within the SPIRE instrument team to extract all prominent Spectral Features from all publicly available SPIRE FTS observations. In this work, we demonstrate the use of the FF information extracted from three observations of the edge-on spiral galaxy NGC 891 to measure the rotation of N ii and C i gas at far-infrared frequencies in complement to radio observations of the [H i] 21-cm line and the CO(1-0) transition as well as optical measurements of Hα. We find that measurements of both N ii and C i gas follow a similar velocity profile to that of H i and Hα showing a correlation between neutral and ionized regions of the interstellar medium in the disc of NGC 891.
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the herschel spire fourier transform spectrometer Spectral Feature finder v rotational measurements of ngc 891
arXiv: Astrophysics of Galaxies, 2020Co-Authors: Chris S Benson, L D Spencer, Jeremy P Scott, I Valtchanov, N HladczukAbstract:The ESA Herschel Spectral and Photometric Imaging Receiver (SPIRE) Fourier Transform Spectrometer (FTS) Spectral Feature Finder (FF) project is an automated Spectral Feature fitting routine developed within the SPIRE instrument team to extract all prominent Spectral Features from all publicly available SPIRE FTS observations. In this work, we demonstrate the use of the FF information extracted from three observations of the edge-on spiral galaxy NGC 891 to measure the rotation of NII and CI gas at Far-infrared frequencies in complement to radio observations of the HI 21cm line and the CO(1-0) transition as well as optical measurements of Halpha. We find that measurements of both NII and CI gas follow a similar velocity profile to that of HI and Halpha showing a correlation between neutral and ionized regions of the interstellar medium (ISM) in the disk of NGC 891.
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the herschel spire fourier transform spectrometer Spectral Feature finder iii line identification and off axis spectra
Monthly Notices of the Royal Astronomical Society, 2020Co-Authors: Chris S Benson, N Hladczuk, L D Spencer, A Robb, Jeremy P Scott, I Valtchanov, R Hopwood, D A NaylorAbstract:The ESA Herschel Spectral and Photometric Imaging Receiver (SPIRE) Fourier Transform Spectrometer (FTS) Spectral Feature Finder (FF) project is an automated Spectral Feature fitting routine developed within the SPIRE instrument team to extract all prominent Spectral Features from all publicly available SPIRE FTS observations. We present the extension of the FF to include the off-axis detectors of the FTS in sparsely sampled single-pointing observations, the results of which have been ingested into the catalogue. We also present the results from an automated routine for identifications of the atomic/molecular transitions that correspond to the Spectral Features extracted by the FF. We use a template of 307 atomic fine structure and molecular lines that are commonly found in SPIRE FTS spectra for the cross-match. The routine makes use of information provided by the line identification to search for low signal-to-noise ratio Features that have been excluded or missed by the iterative FF. In total, the atomic/molecular transitions of 178,942 lines are identified (corresponding to 83% of the entire FF catalogue), and an additional 33,840 Spectral lines associated with missing Features from SPIRE FTS observations are added to the FF catalogue.
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the herschel spire fourier transform spectrometer Spectral Feature finder iv neutral carbon detection in the spire fts spectra
Monthly Notices of the Royal Astronomical Society, 2020Co-Authors: Jeremy P Scott, L D Spencer, I Valtchanov, R Hopwood, D A NaylorAbstract:The SPIRE FTS Spectral Feature Finder (FF), developed within the Herschel Spectral and Photometric Imaging Receiver (SPIRE) Fourier Transform Spectrometer (FTS) instrument team, is an automated Spectral Feature fitting routine that attempts to find significant Features in SPIRE FTS spectra. The $^3$P$_1$ - $^3$P$_0$ and $^3$P$_2$ - $^3$P$_1$ neutral carbon fine structure lines are common Features in carbon rich far-infrared astrophysical sources. These Features can be difficult to detect using an automated Feature detection routine due to their typically low amplitude and line blending. In this paper we describe and validate the FF sub-routine designed to detect the neutral carbon emission observed in SPIRE Spectral data.
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the herschel spire fourier transform spectrometer Spectral Feature finder i the Spectral Feature finder and catalogue
Monthly Notices of the Royal Astronomical Society, 2020Co-Authors: Chris S Benson, N Hladczuk, L D Spencer, Jeremy P Scott, I Valtchanov, R Hopwood, N Marchili, E T PolehamptonAbstract:We provide a detailed description of the Herschel-SPIRE Fourier Transform Spectrometer (FTS) Spectral Feature Finder (FF). The FF is an automated process designed to extract significant Spectral Features from SPIRE FTS data products. Optimising the number of Features found in SPIRE-FTS spectra is challenging. The wide SPIRE-FTS frequency range (447-1568 GHz) leads to many molecular species and atomic fine structure lines falling within the observed bands. As the best Spectral resolution of the SPIRE-FTS is ~1.2 GHz, there can be significant line blending, depending on the source type. In order to find, both efficiently and reliably, Features in spectra associated with a wide range of sources, the FF iteratively searches for peaks over a number of signal-to-noise ratio (SNR) thresholds. For each threshold, newly identified Features are rigorously checked before being added to the fitting model. At the end of each iteration, the FF simultaneously fits the continuum and Features found, with the resulting residual spectrum used in the next iteration. The final FF products report the frequency of the Features found and the associated SNRs. Line flux determination is not included as part of the FF products, as extracting reliable line flux from SPIRE-FTS data is a complex process that requires careful evaluation and analysis of the spectra on a case-by-case basis. The FF results are 100% complete for Features with SNR greater than 10 and 50-70% complete at SNR of 5. The FF code and all FF products are publicly available via the Herschel Science Archive.
R Hopwood - One of the best experts on this subject based on the ideXlab platform.
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the herschel spire fourier transform spectrometer Spectral Feature finder iii line identification and off axis spectra
Monthly Notices of the Royal Astronomical Society, 2020Co-Authors: Chris S Benson, N Hladczuk, L D Spencer, A Robb, Jeremy P Scott, I Valtchanov, R Hopwood, D A NaylorAbstract:The ESA Herschel Spectral and Photometric Imaging Receiver (SPIRE) Fourier Transform Spectrometer (FTS) Spectral Feature Finder (FF) project is an automated Spectral Feature fitting routine developed within the SPIRE instrument team to extract all prominent Spectral Features from all publicly available SPIRE FTS observations. We present the extension of the FF to include the off-axis detectors of the FTS in sparsely sampled single-pointing observations, the results of which have been ingested into the catalogue. We also present the results from an automated routine for identifications of the atomic/molecular transitions that correspond to the Spectral Features extracted by the FF. We use a template of 307 atomic fine structure and molecular lines that are commonly found in SPIRE FTS spectra for the cross-match. The routine makes use of information provided by the line identification to search for low signal-to-noise ratio Features that have been excluded or missed by the iterative FF. In total, the atomic/molecular transitions of 178,942 lines are identified (corresponding to 83% of the entire FF catalogue), and an additional 33,840 Spectral lines associated with missing Features from SPIRE FTS observations are added to the FF catalogue.
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the herschel spire fourier transform spectrometer Spectral Feature finder iv neutral carbon detection in the spire fts spectra
Monthly Notices of the Royal Astronomical Society, 2020Co-Authors: Jeremy P Scott, L D Spencer, I Valtchanov, R Hopwood, D A NaylorAbstract:The SPIRE FTS Spectral Feature Finder (FF), developed within the Herschel Spectral and Photometric Imaging Receiver (SPIRE) Fourier Transform Spectrometer (FTS) instrument team, is an automated Spectral Feature fitting routine that attempts to find significant Features in SPIRE FTS spectra. The $^3$P$_1$ - $^3$P$_0$ and $^3$P$_2$ - $^3$P$_1$ neutral carbon fine structure lines are common Features in carbon rich far-infrared astrophysical sources. These Features can be difficult to detect using an automated Feature detection routine due to their typically low amplitude and line blending. In this paper we describe and validate the FF sub-routine designed to detect the neutral carbon emission observed in SPIRE Spectral data.
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the herschel spire fourier transform spectrometer Spectral Feature finder i the Spectral Feature finder and catalogue
Monthly Notices of the Royal Astronomical Society, 2020Co-Authors: Chris S Benson, N Hladczuk, L D Spencer, Jeremy P Scott, I Valtchanov, R Hopwood, N Marchili, E T PolehamptonAbstract:We provide a detailed description of the Herschel-SPIRE Fourier Transform Spectrometer (FTS) Spectral Feature Finder (FF). The FF is an automated process designed to extract significant Spectral Features from SPIRE FTS data products. Optimising the number of Features found in SPIRE-FTS spectra is challenging. The wide SPIRE-FTS frequency range (447-1568 GHz) leads to many molecular species and atomic fine structure lines falling within the observed bands. As the best Spectral resolution of the SPIRE-FTS is ~1.2 GHz, there can be significant line blending, depending on the source type. In order to find, both efficiently and reliably, Features in spectra associated with a wide range of sources, the FF iteratively searches for peaks over a number of signal-to-noise ratio (SNR) thresholds. For each threshold, newly identified Features are rigorously checked before being added to the fitting model. At the end of each iteration, the FF simultaneously fits the continuum and Features found, with the resulting residual spectrum used in the next iteration. The final FF products report the frequency of the Features found and the associated SNRs. Line flux determination is not included as part of the FF products, as extracting reliable line flux from SPIRE-FTS data is a complex process that requires careful evaluation and analysis of the spectra on a case-by-case basis. The FF results are 100% complete for Features with SNR greater than 10 and 50-70% complete at SNR of 5. The FF code and all FF products are publicly available via the Herschel Science Archive.
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The Herschel/SPIRE Spectral Feature Finder: Updated Feature Catalogues
Light Energy and the Environment 2018 (E2 FTS HISE SOLAR SSL), 2018Co-Authors: Jeremy P Scott, Chris S Benson, I Valtchanov, R Hopwood, Locke D. Spencer, David A. Naylor, N. HładczukAbstract:We present an analysis of the updated publicly available Herschel SPIRE Spectral Feature Finder data products, focusing primarily on mapping observations, radial velocity estimates, and neutral carbon detection.
Chris S Benson - One of the best experts on this subject based on the ideXlab platform.
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The Herschel SPIRE Fourier Transform Spectrometer Spectral Feature Finder – V. Rotational measurements of NGC 891
Monthly Notices of the Royal Astronomical Society, 2020Co-Authors: Chris S Benson, Jeremy P Scott, I Valtchanov, Locke D. Spencer, N HladczukAbstract:ABSTRACT The ESA Herschel Spectral and Photometric Imaging Receiver (SPIRE) Fourier Transform Spectrometer (FTS) Spectral Feature Finder (FF) project is an automated Spectral Feature fitting routine developed within the SPIRE instrument team to extract all prominent Spectral Features from all publicly available SPIRE FTS observations. In this work, we demonstrate the use of the FF information extracted from three observations of the edge-on spiral galaxy NGC 891 to measure the rotation of N ii and C i gas at far-infrared frequencies in complement to radio observations of the [H i] 21-cm line and the CO(1-0) transition as well as optical measurements of Hα. We find that measurements of both N ii and C i gas follow a similar velocity profile to that of H i and Hα showing a correlation between neutral and ionized regions of the interstellar medium in the disc of NGC 891.
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the herschel spire fourier transform spectrometer Spectral Feature finder v rotational measurements of ngc 891
arXiv: Astrophysics of Galaxies, 2020Co-Authors: Chris S Benson, L D Spencer, Jeremy P Scott, I Valtchanov, N HladczukAbstract:The ESA Herschel Spectral and Photometric Imaging Receiver (SPIRE) Fourier Transform Spectrometer (FTS) Spectral Feature Finder (FF) project is an automated Spectral Feature fitting routine developed within the SPIRE instrument team to extract all prominent Spectral Features from all publicly available SPIRE FTS observations. In this work, we demonstrate the use of the FF information extracted from three observations of the edge-on spiral galaxy NGC 891 to measure the rotation of NII and CI gas at Far-infrared frequencies in complement to radio observations of the HI 21cm line and the CO(1-0) transition as well as optical measurements of Halpha. We find that measurements of both NII and CI gas follow a similar velocity profile to that of HI and Halpha showing a correlation between neutral and ionized regions of the interstellar medium (ISM) in the disk of NGC 891.
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the herschel spire fourier transform spectrometer Spectral Feature finder iii line identification and off axis spectra
Monthly Notices of the Royal Astronomical Society, 2020Co-Authors: Chris S Benson, N Hladczuk, L D Spencer, A Robb, Jeremy P Scott, I Valtchanov, R Hopwood, D A NaylorAbstract:The ESA Herschel Spectral and Photometric Imaging Receiver (SPIRE) Fourier Transform Spectrometer (FTS) Spectral Feature Finder (FF) project is an automated Spectral Feature fitting routine developed within the SPIRE instrument team to extract all prominent Spectral Features from all publicly available SPIRE FTS observations. We present the extension of the FF to include the off-axis detectors of the FTS in sparsely sampled single-pointing observations, the results of which have been ingested into the catalogue. We also present the results from an automated routine for identifications of the atomic/molecular transitions that correspond to the Spectral Features extracted by the FF. We use a template of 307 atomic fine structure and molecular lines that are commonly found in SPIRE FTS spectra for the cross-match. The routine makes use of information provided by the line identification to search for low signal-to-noise ratio Features that have been excluded or missed by the iterative FF. In total, the atomic/molecular transitions of 178,942 lines are identified (corresponding to 83% of the entire FF catalogue), and an additional 33,840 Spectral lines associated with missing Features from SPIRE FTS observations are added to the FF catalogue.
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the herschel spire fourier transform spectrometer Spectral Feature finder i the Spectral Feature finder and catalogue
Monthly Notices of the Royal Astronomical Society, 2020Co-Authors: Chris S Benson, N Hladczuk, L D Spencer, Jeremy P Scott, I Valtchanov, R Hopwood, N Marchili, E T PolehamptonAbstract:We provide a detailed description of the Herschel-SPIRE Fourier Transform Spectrometer (FTS) Spectral Feature Finder (FF). The FF is an automated process designed to extract significant Spectral Features from SPIRE FTS data products. Optimising the number of Features found in SPIRE-FTS spectra is challenging. The wide SPIRE-FTS frequency range (447-1568 GHz) leads to many molecular species and atomic fine structure lines falling within the observed bands. As the best Spectral resolution of the SPIRE-FTS is ~1.2 GHz, there can be significant line blending, depending on the source type. In order to find, both efficiently and reliably, Features in spectra associated with a wide range of sources, the FF iteratively searches for peaks over a number of signal-to-noise ratio (SNR) thresholds. For each threshold, newly identified Features are rigorously checked before being added to the fitting model. At the end of each iteration, the FF simultaneously fits the continuum and Features found, with the resulting residual spectrum used in the next iteration. The final FF products report the frequency of the Features found and the associated SNRs. Line flux determination is not included as part of the FF products, as extracting reliable line flux from SPIRE-FTS data is a complex process that requires careful evaluation and analysis of the spectra on a case-by-case basis. The FF results are 100% complete for Features with SNR greater than 10 and 50-70% complete at SNR of 5. The FF code and all FF products are publicly available via the Herschel Science Archive.
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the herschel spire fourier transform spectrometer Spectral Feature finder ii estimating radial velocity of spire Spectral observation sources
Monthly Notices of the Royal Astronomical Society, 2020Co-Authors: Jeremy P Scott, Chris S Benson, N Hladczuk, L D Spencer, I Valtchanov, Rosalind HopwoodAbstract:The Herschel SPIRE FTS Spectral Feature Finder (FF) detects significant Spectral Features within SPIRE spectra and employs two routines, and external references, to estimate source radial velocity. The first routine is based on the identification of rotational CO emission, the second cross-correlates detected Features with a line template containing most of the characteristic lines in typical far infra-red observations. In this paper, we outline and validate these routines, summarise the results as they pertain to the FF, and comment on how external references were incorporated.
N Hladczuk - One of the best experts on this subject based on the ideXlab platform.
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The Herschel SPIRE Fourier Transform Spectrometer Spectral Feature Finder – V. Rotational measurements of NGC 891
Monthly Notices of the Royal Astronomical Society, 2020Co-Authors: Chris S Benson, Jeremy P Scott, I Valtchanov, Locke D. Spencer, N HladczukAbstract:ABSTRACT The ESA Herschel Spectral and Photometric Imaging Receiver (SPIRE) Fourier Transform Spectrometer (FTS) Spectral Feature Finder (FF) project is an automated Spectral Feature fitting routine developed within the SPIRE instrument team to extract all prominent Spectral Features from all publicly available SPIRE FTS observations. In this work, we demonstrate the use of the FF information extracted from three observations of the edge-on spiral galaxy NGC 891 to measure the rotation of N ii and C i gas at far-infrared frequencies in complement to radio observations of the [H i] 21-cm line and the CO(1-0) transition as well as optical measurements of Hα. We find that measurements of both N ii and C i gas follow a similar velocity profile to that of H i and Hα showing a correlation between neutral and ionized regions of the interstellar medium in the disc of NGC 891.
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the herschel spire fourier transform spectrometer Spectral Feature finder v rotational measurements of ngc 891
arXiv: Astrophysics of Galaxies, 2020Co-Authors: Chris S Benson, L D Spencer, Jeremy P Scott, I Valtchanov, N HladczukAbstract:The ESA Herschel Spectral and Photometric Imaging Receiver (SPIRE) Fourier Transform Spectrometer (FTS) Spectral Feature Finder (FF) project is an automated Spectral Feature fitting routine developed within the SPIRE instrument team to extract all prominent Spectral Features from all publicly available SPIRE FTS observations. In this work, we demonstrate the use of the FF information extracted from three observations of the edge-on spiral galaxy NGC 891 to measure the rotation of NII and CI gas at Far-infrared frequencies in complement to radio observations of the HI 21cm line and the CO(1-0) transition as well as optical measurements of Halpha. We find that measurements of both NII and CI gas follow a similar velocity profile to that of HI and Halpha showing a correlation between neutral and ionized regions of the interstellar medium (ISM) in the disk of NGC 891.
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the herschel spire fourier transform spectrometer Spectral Feature finder iii line identification and off axis spectra
Monthly Notices of the Royal Astronomical Society, 2020Co-Authors: Chris S Benson, N Hladczuk, L D Spencer, A Robb, Jeremy P Scott, I Valtchanov, R Hopwood, D A NaylorAbstract:The ESA Herschel Spectral and Photometric Imaging Receiver (SPIRE) Fourier Transform Spectrometer (FTS) Spectral Feature Finder (FF) project is an automated Spectral Feature fitting routine developed within the SPIRE instrument team to extract all prominent Spectral Features from all publicly available SPIRE FTS observations. We present the extension of the FF to include the off-axis detectors of the FTS in sparsely sampled single-pointing observations, the results of which have been ingested into the catalogue. We also present the results from an automated routine for identifications of the atomic/molecular transitions that correspond to the Spectral Features extracted by the FF. We use a template of 307 atomic fine structure and molecular lines that are commonly found in SPIRE FTS spectra for the cross-match. The routine makes use of information provided by the line identification to search for low signal-to-noise ratio Features that have been excluded or missed by the iterative FF. In total, the atomic/molecular transitions of 178,942 lines are identified (corresponding to 83% of the entire FF catalogue), and an additional 33,840 Spectral lines associated with missing Features from SPIRE FTS observations are added to the FF catalogue.
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the herschel spire fourier transform spectrometer Spectral Feature finder i the Spectral Feature finder and catalogue
Monthly Notices of the Royal Astronomical Society, 2020Co-Authors: Chris S Benson, N Hladczuk, L D Spencer, Jeremy P Scott, I Valtchanov, R Hopwood, N Marchili, E T PolehamptonAbstract:We provide a detailed description of the Herschel-SPIRE Fourier Transform Spectrometer (FTS) Spectral Feature Finder (FF). The FF is an automated process designed to extract significant Spectral Features from SPIRE FTS data products. Optimising the number of Features found in SPIRE-FTS spectra is challenging. The wide SPIRE-FTS frequency range (447-1568 GHz) leads to many molecular species and atomic fine structure lines falling within the observed bands. As the best Spectral resolution of the SPIRE-FTS is ~1.2 GHz, there can be significant line blending, depending on the source type. In order to find, both efficiently and reliably, Features in spectra associated with a wide range of sources, the FF iteratively searches for peaks over a number of signal-to-noise ratio (SNR) thresholds. For each threshold, newly identified Features are rigorously checked before being added to the fitting model. At the end of each iteration, the FF simultaneously fits the continuum and Features found, with the resulting residual spectrum used in the next iteration. The final FF products report the frequency of the Features found and the associated SNRs. Line flux determination is not included as part of the FF products, as extracting reliable line flux from SPIRE-FTS data is a complex process that requires careful evaluation and analysis of the spectra on a case-by-case basis. The FF results are 100% complete for Features with SNR greater than 10 and 50-70% complete at SNR of 5. The FF code and all FF products are publicly available via the Herschel Science Archive.
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the herschel spire fourier transform spectrometer Spectral Feature finder ii estimating radial velocity of spire Spectral observation sources
Monthly Notices of the Royal Astronomical Society, 2020Co-Authors: Jeremy P Scott, Chris S Benson, N Hladczuk, L D Spencer, I Valtchanov, Rosalind HopwoodAbstract:The Herschel SPIRE FTS Spectral Feature Finder (FF) detects significant Spectral Features within SPIRE spectra and employs two routines, and external references, to estimate source radial velocity. The first routine is based on the identification of rotational CO emission, the second cross-correlates detected Features with a line template containing most of the characteristic lines in typical far infra-red observations. In this paper, we outline and validate these routines, summarise the results as they pertain to the FF, and comment on how external references were incorporated.
