The Experts below are selected from a list of 43599 Experts worldwide ranked by ideXlab platform
A W Thomas - One of the best experts on this subject based on the ideXlab platform.
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γz box Corrections to weak charges of heavy nuclei in atomic parity violation
Physical Review Letters, 2012Co-Authors: P G Blunden, W Melnitchouk, A W ThomasAbstract:We present a new dispersive formulation of the {gamma}-Z box radiative Corrections to weak charges of bound protons and neutrons in atomic parity violation measurements on heavy nuclei such as {sup 133}Cs and {sup 213}Ra. We evaluate for the first time a small but important Additional Correction arising from Pauli blocking of nucleons in a heavy nucleus. Overall, we find a significant shift in the {gamma}-Z Correction to the weak charge of {sup 133}Cs, approximately 4 times larger than the current uncertainty on the value of sin{sup 2}({theta}{sub W}), but with a reduced error compared with earlier estimates.
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isovector emc effect and the nutev anomaly
Physical Review Letters, 2009Co-Authors: I. C. Cloët, Wolfgang Bentz, A W ThomasAbstract:A neutron or proton excess in nuclei leads to an isovector-vector mean field which, through its coupling to the quarks in a bound nucleon, implies a shift in the quark distributions with respect to the Bjorken scaling variable. We show that this result leads to an Additional Correction to the NuTeV measurement of sin{sup 2}theta{sub W}. The sign of this Correction is largely model independent and acts to reduce their result. Explicit calculation in nuclear matter within a covariant and confining Nambu-Jona-Lasinio model predicts that this vector field Correction may account for a substantial fraction of the NuTeV anomaly. We are therefore led to offer a new interpretation of the NuTeV measurement, namely, that it provides further evidence for the medium modification of the bound nucleon wave function.
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Isovector EMC effect and the NuTeV anomaly
Physical Review Letters, 2009Co-Authors: I. C. Cloët, Wolfram Bentz, A W ThomasAbstract:A neutron or proton excess in nuclei leads to an isovector-vector mean field which, through its coupling to the quarks in a bound nucleon, implies a shift in the quark distributions with respect to the Bjorken scaling variable. We show that this result leads to an Additional Correction to the NuTeV measurement of sin2W. The sign of this Correction is largely model independent and acts to reduce their result. Explicit calculation in nuclear matter within a covariant and confining Nambu–Jona-Lasinio model predicts that this vector field Correction may account for a substantial fraction of the NuTeV anomaly. We are therefore led to offer a new interpretation of the NuTeV measurement, namely, that it provides further evidence for the medium modification of the bound nucleon wave function.
C M Adhikari - One of the best experts on this subject based on the ideXlab platform.
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relativistic and radiative Corrections to the dynamic stark shift gauge invariance and transition currents in the velocity gauge
Physical Review A, 2018Co-Authors: Ulrich D Jentschura, C M AdhikariAbstract:We investigate the gauge invariance of the dynamic (ac) Stark shift under "hybrid" gauge transformations from the "length" (E.r) to the "velocity" (A.p) gauge. By a "hybrid" gauge transformation, we understand a transformation in which the scalar and vector potentials are modified, but the wave function remains unaltered. The gauge invariance of the leading term is well known, while we here show that gauge invariance under perturbations holds only if one takes into account an Additional Correction to the transition current, which persists only in the velocity gauge. We find a general expression for this current, and apply the formalism to radiative and relativistic Corrections to the dynamic Stark effect, which is described by the sum of two polarizability matrix elements.
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relativistic and radiative Corrections to the dynamic stark shift gauge invariance and transition currents in the velocity gauge
Physical Review A, 2018Co-Authors: Ulrich D Jentschura, C M AdhikariAbstract:We investigate the gauge invariance of the dynamic (ac) Stark shift under ``hybrid'' gauge transformations from the ``length'' ($\stackrel{P\vec}{E}\ifmmode\cdot\else\textperiodcentered\fi{}\stackrel{P\vec}{r}$) to the ``velocity'' ($\stackrel{P\vec}{A}\ifmmode\cdot\else\textperiodcentered\fi{}\stackrel{P\vec}{p}$) gauge. By a ``hybrid'' gauge transformation, we understand a transformation in which the scalar and vector potentials are modified, but the wave function remains unaltered. The gauge invariance of the leading term is well known, while we here show that gauge invariance under perturbations holds only if one takes into account an Additional Correction to the transition current, which persists only in the velocity gauge. We find a general expression for this current, and apply the formalism to radiative and relativistic Corrections to the dynamic Stark effect, which is described by the sum of two polarizability matrix elements.
Jacques Devriendt - One of the best experts on this subject based on the ideXlab platform.
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renal replacement therapy is an independent risk factor for mortality in critically ill patients with acute kidney injury
Critical Care, 2010Co-Authors: Monique M Elseviers, R L Lins, Patricia Van Der Niepen, Eric Hoste, Manu L N G Malbrain, Pierre Damas, Jacques DevriendtAbstract:Introduction: Outcome studies in patients with acute kidney injury (AKI) have focused on differences between modalities of renal replacement therapy (RRT). The outcome of conservative treatment, however, has never been compared with RRT. Methods: Nine Belgian intensive care units (ICUs) included all adult patients consecutively admitted with serum creatinine >2 mg/dl. Included treatment options were conservative treatment and intermittent or continuous RRT. Disease severity was determined using the Stuivenberg Hospital Acute Renal Failure (SHARF) score. Outcome parameters studied were mortality, hospital length of stay and renal recovery at hospital discharge. Results: Out of 1,303 included patients, 650 required RRT (58% intermittent, 42% continuous RRT). Overall results showed a higher mortality (43% versus 58%) as well as a longer ICU and hospital stay in RRT patients compared to conservative treatment. Using the SHARF score for adjustment of disease severity, an increased risk of death for RRT compared to conservative treatment of RR = 1.75 (95% CI: 1.4 to 2.3) was found. Additional Correction for other severity parameters (Acute Physiology And Chronic Health Evaluation II (APACHE II), Sequential Organ Failure Assessment (SOFA)), age, type of AKI and clinical conditions confirmed the higher mortality in the RRT group. Conclusions: The SHARF study showed that the higher mortality expected in AKI patients receiving RRT versus conservative treatment can not only be explained by a higher disease severity in the RRT group, even after multiple Corrections. A more critical approach to the need for RRT in AKI patients seems to be warranted.
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renal replacement therapy is an independent risk factor for mortality in critically ill patients with acute kidney injury
Critical Care, 2010Co-Authors: Monique M Elseviers, R L Lins, Patricia Van Der Niepen, Eric Hoste, Manu L N G Malbrain, Pierre Damas, Jacques DevriendtAbstract:Outcome studies in patients with acute kidney injury (AKI) have focused on differences between modalities of renal replacement therapy (RRT). The outcome of conservative treatment, however, has never been compared with RRT. Nine Belgian intensive care units (ICUs) included all adult patients consecutively admitted with serum creatinine >2 mg/dl. Included treatment options were conservative treatment and intermittent or continuous RRT. Disease severity was determined using the Stuivenberg Hospital Acute Renal Failure (SHARF) score. Outcome parameters studied were mortality, hospital length of stay and renal recovery at hospital discharge. Out of 1,303 included patients, 650 required RRT (58% intermittent, 42% continuous RRT). Overall results showed a higher mortality (43% versus 58%) as well as a longer ICU and hospital stay in RRT patients compared to conservative treatment. Using the SHARF score for adjustment of disease severity, an increased risk of death for RRT compared to conservative treatment of RR = 1.75 (95% CI: 1.4 to 2.3) was found. Additional Correction for other severity parameters (Acute Physiology And Chronic Health Evaluation II (APACHE II), Sequential Organ Failure Assessment (SOFA)), age, type of AKI and clinical conditions confirmed the higher mortality in the RRT group. The SHARF study showed that the higher mortality expected in AKI patients receiving RRT versus conservative treatment can not only be explained by a higher disease severity in the RRT group, even after multiple Corrections. A more critical approach to the need for RRT in AKI patients seems to be warranted.
I. C. Cloët - One of the best experts on this subject based on the ideXlab platform.
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isovector emc effect and the nutev anomaly
Physical Review Letters, 2009Co-Authors: I. C. Cloët, Wolfgang Bentz, A W ThomasAbstract:A neutron or proton excess in nuclei leads to an isovector-vector mean field which, through its coupling to the quarks in a bound nucleon, implies a shift in the quark distributions with respect to the Bjorken scaling variable. We show that this result leads to an Additional Correction to the NuTeV measurement of sin{sup 2}theta{sub W}. The sign of this Correction is largely model independent and acts to reduce their result. Explicit calculation in nuclear matter within a covariant and confining Nambu-Jona-Lasinio model predicts that this vector field Correction may account for a substantial fraction of the NuTeV anomaly. We are therefore led to offer a new interpretation of the NuTeV measurement, namely, that it provides further evidence for the medium modification of the bound nucleon wave function.
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Isovector EMC effect and the NuTeV anomaly
Physical Review Letters, 2009Co-Authors: I. C. Cloët, Wolfram Bentz, A W ThomasAbstract:A neutron or proton excess in nuclei leads to an isovector-vector mean field which, through its coupling to the quarks in a bound nucleon, implies a shift in the quark distributions with respect to the Bjorken scaling variable. We show that this result leads to an Additional Correction to the NuTeV measurement of sin2W. The sign of this Correction is largely model independent and acts to reduce their result. Explicit calculation in nuclear matter within a covariant and confining Nambu–Jona-Lasinio model predicts that this vector field Correction may account for a substantial fraction of the NuTeV anomaly. We are therefore led to offer a new interpretation of the NuTeV measurement, namely, that it provides further evidence for the medium modification of the bound nucleon wave function.
Daisuke Iono - One of the best experts on this subject based on the ideXlab platform.
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a radio to mm census of star forming galaxies in protocluster 4c23 56 at z 2 5 gas mass and its fraction revealed with alma
The Astrophysical Journal, 2017Co-Authors: Minju Lee, Ichi Tanaka, Ryohei Kawabe, Kotaro Kohno, Tadayuki Kodama, Masaru Kajisawa, Min S Yun, Kouichiro Nakanishi, Daisuke IonoAbstract:We investigate gas contents of star-forming galaxies associated with protocluster 4C23.56 at z = 2.49 by using the redshifted CO (3-2) and 1.1 mm dust continuum with the Atacama Large Millimeter/submillimeter Array. The observations unveil seven CO detections out of 22 targeted Hα emitters (HAEs) and four out of 19 in 1.1 mm dust continuum. They have high stellar mass ({M}\star > 4× {10}10 M ⊙) and exhibit a specific star-formation rate typical of main-sequence star-forming galaxies at z˜ 2.5. Different gas-mass estimators from CO (3-2) and 1.1 mm yield consistent values for simultaneous detections. The gas mass ({M}{gas}) and gas fraction ({f}{gas}) are comparable to those of field galaxies, with {M}{gas}=[0.3,1.8]× {10}11× ({α }{CO}/(4.36× A(Z))) {M}⊙ , where {α }{CO} is the CO-to-H2 conversion factor and A(Z) is the Additional Correction factor for the metallicity dependence of {α }{CO}, and =0.53+/- 0.07 from CO (3-2). Our measurements place a constraint on the cosmic gas density of high-z protoclusters, indicating that the protocluster is characterized by a gas density higher than that of the general fields by an order of magnitude. We found ρ ({H}2)˜ 5× {10}9 {M}⊙ {{Mpc}}-3 with the CO(3-2) detections. The five ALMA CO detections occur in the region of highest galaxy surface density, where the density positively correlates with global star-forming efficiency (SFE) and stellar mass. Such correlations possibly indicate a critical role of the environment on early galaxy evolution at high-z protoclusters, though future observations are necessary for confirmation.
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a radio to mm census of star forming galaxies in protocluster 4c23 56 at z 2 5 gas mass and its fraction revealed with alma
arXiv: Astrophysics of Galaxies, 2017Co-Authors: Minju Lee, Ichi Tanaka, Ryohei Kawabe, Kotaro Kohno, Tadayuki Kodama, Masaru Kajisawa, Min S Yun, Kouichiro Nakanishi, Daisuke IonoAbstract:We investigate gas contents of star-forming galaxies associated with protocluster 4C23.56 at z = 2.49 by using the redshifted CO(3-2) and 1.1 mm dust continuum with the Atacama Large Millimeter/submillimeter Array. The observations unveil seven CO detections out of 22 targeted H$\alpha$ emitters (HAEs) and four out of 19 in 1.1 mm dust continuum. They have high stellar mass ($M_{\star}>4\times 10^{10}$ $M_{\odot}$) and exhibit a specific star-formation rate typical of main-sequence star forming galaxies at $z\sim2.5$. Different gas mass estimators from CO(3-2) and 1.1 mm yield consistent values for simultaneous detections. The gas mass ($M_{\rm gas}$) and gas fraction ($f_{\rm gas}$) are comparable to those of field galaxies, with $M_{\rm gas}=[0.3, 1.8]\times10^{11} \times (\alpha_{\rm CO}/(4.36\times A(Z)$)) M$_{\odot}$, where $\alpha_{\rm CO}$ is the CO-to-H$_2$ conversion factor and $A(Z)$ the Additional Correction factor for the metallicity dependence of $\alpha_{\rm CO}$, and $\langle f_{\rm gas}\rangle = 0.53 \pm 0.07$ from CO(3-2). Our measurements place a constraint on the cosmic gas density of high-$z$ protoclusters, indicating the protocluster is characterized by a gas density higher than that of the general fields by an order of magnitude. We found $\rho (H_2)\sim 5 \times 10^9 \,M_{\odot}\,{\rm Mpc^{-3}}$ with the CO(3-2) detections. The five ALMA CO detections occur in the region of highest galaxy surface density, where the density positively correlates with global star-forming efficiency (SFE) and stellar mass. Such correlations imply a potentially critical role of environment on early galaxy evolution at high-z protoclusters, although future observations are necessary for confirmation.