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GW150914: The Advanced LIGO Detectors in the Era of First Discoveries
Abbott, B. P.,Abbott, R.,Abbott, T. D.,Abernathy, M. R.,Acernese, F.,Ackley, K.,Adams, C.,Adams, T.,Addesso, P.,Adhikari, R. X.,Adya, V. B.,Affeldt, C.,Agathos, M.,Agatsuma, K.,Aggarwal, N.,Aguiar, O. American Physical Society 2016 Physical Review Letters Vol.116 No.13
<P>Following a major upgrade, the two advanced detectors of the Laser Interferometer Gravitational-wave Observatory (LIGO) held their first observation run between September 2015 and January 2016. With a strain sensitivity of 10(-23) / root Hz at 100 Hz, the product of observable volume and measurement time exceeded that of all previous runs within the first 16 days of coincident observation. On September 14, 2015, the Advanced LIGO detectors observed a transient gravitational-wave signal determined to be the coalescence of two black holes [B. P. Abbott et al., Phys. Rev. Lett. 116, 061102 (2016)], launching the era of gravitational-wave astronomy. The event, GW150914, was observed with a combined signal-to-noise ratio of 24 in coincidence by the two detectors. Here, we present the main features of the detectors that enabled this observation. At full sensitivity, the Advanced LIGO detectors are designed to deliver another factor of 3 improvement in the signal-to-noise ratio for binary black hole systems similar in mass to GW150914.</P>
Bs0lifetime measurement in theCP-odd decay channelBs0→J/ψ f0(980)
Abazov, V. M.,Abbott, B.,Acharya, B. S.,Adams, M.,Adams, T.,Agnew, J. P.,Alexeev, G. D.,Alkhazov, G.,Alton, A.,Askew, A.,Atkins, S.,Augsten, K.,Aushev, V.,Aushev, Y.,Avila, C.,Badaud, F.,Bagby, L.,Bal American Physical Society 2016 Physical Review D Vol.94 No.1
<P>The lifetime of the B-s(0) meson is measured in the decay channel B-s(0) -> J/Psi pi(+)pi(-) with 880 <= M pi+pi- <= 1080 MeV/c(2), which is mainly a CP-odd state and dominated by the f(0)(980) resonance. In 10.4 fb(-1) of data collected with the D0 detector in Run II of the Tevatron, the lifetime of the B-s(0) meson is measured to be tau(B-s(0)) = 1.70 +/- 0.14(stat) +/- 0.05(syst) ps. Neglecting CP violation in B-s(0)/(B) over bar (0)(s) mixing, the measurement can be translated into the width of the heavy mass eigenstate of the B-s(0), Gamma(H) = 0.59 +/- 0.05(stat) +/- 0.02(syst) ps(-1).</P>
Study of the X±(5568) state with semileptonic decays of the Bs0 meson
Abazov, V. M.,Abbott, B.,Acharya, B. S.,Adams, M.,Adams, T.,Agnew, J. P.,Alexeev, G. D.,Alkhazov, G.,Alton, A.,Askew, A.,Atkins, S.,Augsten, K.,Aushev, V.,Aushev, Y.,Avila, C.,Badaud, F.,Bagby, L.,Bal American Physical Society 2018 Physical Review D Vol.97 No.9
<P>We present a study of the X-+/-(5568) using semileptonic decays of the B-s(0) meson using the full run II integrated luminosity of 10.4 fb(-1) in proton-antiproton collisions at a center of mass energy of 1.96 TeV collected with the DO detector at the Fermilab Tevatron Collider. We report evidence for a narrow structure, X-+/-(5568), in the decay sequence X-+/-(5568) -> B-s(0) pi(+/-) where B-s(0)-> mu(-/+) (DsX)-X-+/-, D-s(+/-)-> phi pi(+/-)which is consistent with the previous measurement by the DO Collaboration in the hadronic decay mode, X-+/-(5568) -> B-s(0)pi(+/-) where B-s(0 )-> J/psi phi. The mass and width of this state are measured using a combined fit of the hadronic and semileptonic data, yielding m = 5566.9(-3.1)(+3.2)(stat)(-1.2)(+0.6)(syst) MeV/c(2), Gamma = 18.6(-6.1)(+7.9)(stat)(-3.8)(+3.5) (syst) McV/c(2) with a significance of 6.7 sigma.</P>
Constraining the <i>p</i>-Mode-<i>g</i>-Mode Tidal Instability with GW170817
American Physical Society 2019 Physical review letters Vol.122 No.6
<P> We analyze the impact of a proposed tidal instability coupling <I>p</I> modes and <I>g</I> modes within neutron stars on GW170817. This nonresonant instability transfers energy from the orbit of the binary to internal modes of the stars, accelerating the gravitational-wave driven inspiral. We model the impact of this instability on the phasing of the gravitational wave signal using three parameters per star: an overall amplitude, a saturation frequency, and a spectral index. Incorporating these additional parameters, we compute the Bayes factor (ln B_{!pg}^{pg}) comparing our <I>p-g</I> model to a standard one. We find that the observed signal is consistent with waveform models that neglect <I>p-g</I> effects, with ln B_{!pg}^{pg} = 0.03_{-0.58}^{+0.70} (maximum <I>a posteriori</I> and 90% credible region). By injecting simulated signals that do not include <I>p-g</I> effects and recovering them with the <I>p-g</I> model, we show that there is a ? 50% probability of obtaining similar ln B_{!pg}^{pg} even when <I>p-g</I> effects are absent. We find that the <I>p-g</I> amplitude for 1.4 M⊙ neutron stars is constrained to less than a few tenths of the theoretical maximum , with maxima <I>a posteriori</I> near one-tenth this maximum and <I>p-g</I> saturation frequency ~70Hz. This suggests that there are less than a few hundred excited modes, assuming they all saturate by wave breaking. For comparison, theoretical upper bounds suggest ?10<SUP>3</SUP> modes saturating by wave breaking. Thus, the measured constraints only rule out extreme values of the <I>p-g</I> parameters. They also imply that the instability dissipates ?10<SUP>51</SUP> ergs over the entire inspiral, i.e., less than a few percent of the energy radiated as gravitational waves. </P>
Search for theX(4140)state inB+→J/ψϕK+decays with the D0 detector
Abazov, V. M.,Abbott, B.,Acharya, B. S.,Adams, M.,Adams, T.,Agnew, J. P.,Alexeev, G. D.,Alkhazov, G.,Alton, A.,Askew, A.,Atkins, S.,Augsten, K.,Avila, C.,Badaud, F.,Bagby, L.,Baldin, B.,Bandurin, D. V American Physical Society 2014 PHYSICAL REVIEW D - Vol.89 No.1
<P>We investigate the decay B+ -> J/psi phi K+ in a search for the X(4140) state, a narrow threshold resonance in the J/psi phi system. The data sample corresponds to an integrated luminosity of 10.4 fb(-1) of p (p) over bar collisions at root s = 1.96 TeV collected by the D0 experiment at the Fermilab Tevatron collider. We observe a mass peak with a statistical significance of 3.1 standard deviations and measure its invariant mass to be M = 4159.0 +/- 4.3(stat) +/- 6.6(syst) MeV and its width to be Gamma = 19.9 +/- 12.6(stat)(-8.0)(+3.0)(syst) MeV.</P>
Measurement of the direct CP violating charge asymmetry in B±→μ±νμD0 decays
Abazov, V. M.,Abbott, B.,Acharya, B. S.,Adams, M.,Adams, T.,Agnew, J. P.,Alexeev, G. D.,Alkhazov, G.,Alton, A.,Askew, A.,Atkins, S.,Augsten, K.,Aushev, V.,Aushev, Y.,Avila, C.,Badaud, F.,Bagby, L.,Bal American Physical Society 2017 Physical Review D Vol.95 No.3
<P>We present the first measurement of the CP violating charge asymmetry in B-+/- -> mu(+/-)nu D-mu(0) decays using the full Run II integrated luminosity of 10.4 fb(-1) in proton-antiproton collisions collected with the D0 detector at the Fermilab Tevatron Collider. We measure a difference in the yield of B- and B+ mesons in these decays by fitting the reconstructed invariant mass distributions. This results in an asymmetry of A(mu D0) = [-0.14 +/- 0.20] %, which is consistent with standard model predictions.</P>
Association of brain heptachlor epoxide and other organochlorine compounds with lewy pathology
Ross, G. Webster,Abbott, Robert D.,Petrovitch, Helen,Duda, John E.,Tanner, Caroline M.,Zarow, Chris,Uyehara‐,Lock, Jane H.,Masaki, Kamal H.,Launer, Lenore J.,Studabaker, William B.,White, Lon R. John Wiley Sons, Inc. 2019 Movement disorders Vol.34 No.2
<P><B>ABSTRACT</B></P><P><B>Background</B></P><P>Organochlorine pesticides are associated with an increased risk of Parkinson's disease. A preliminary analysis from the Honolulu‐Asia Aging Study suggested that heptachlor epoxide, a metabolite from an organochlorine pesticide extensively used in Hawaii, may be especially important. This was a cross sectional analysis to evaluate the association of heptachlor epoxide and other organochlorine compounds with Lewy pathology in an expanded survey of brain organochlorine residues from the longitudinal Honolulu‐Asia Aging Study.</P><P><B>Methods</B></P><P>Organochlorines were measured in frozen occipital or temporal lobes in 705 brains using gas chromatography with mass spectrometry. Lewy pathology was identified using hematoxylin and eosin‐ and α‐synuclein immunochemistry‐stained sections from multiple brain regions.</P><P><B>Results</B></P><P>The prevalence of Lewy pathology was nearly doubled in the presence versus the absence of heptachlor epoxide (30.1% versus 16.3%, <I>P</I> < 0.001). Although associations with other compounds were weaker, hexachlorobenzene (<I>P</I> = 0.003) and α‐chlordane (<I>P</I> = 0.007) were also related to Lewy pathology. Most of the latter associations, however, were a result of confounding from heptachlor epoxide. Neither compound was significantly related to Lewy pathology after adjustment for heptachlor epoxide. In contrast, the association of heptachlor epoxide with Lewy pathology remained significant after adjustments for hexachlorobenzene (<I>P</I> = 0.013) or α‐chlordane (<I>P</I> = 0.005). Findings were unchanged after removal of cases of PD and adjustment for age and other characteristics.</P><P><B>Conclusions</B></P><P>Organochlorine pesticides are associated with the presence of Lewy pathology in the brain, even after exclusion of PD cases. Although most of the association is through heptachlor epoxide, the role of other organochlorine compounds is in need of clarification. © 2018 International Parkinson and Movement Disorder Society</P>
Exploring the sensitivity of next generation gravitational wave detectors
Abbott, B P,Abbott, R,Abbott, T D,Abernathy, M R,Ackley, K,Adams, C,Addesso, P,Adhikari, R X,Adya, V B,Affeldt, C,Aggarwal, N,Aguiar, O D,Ain, A,Ajith, P,Allen, B,Altin, P A,Anderson, S B,Anderson, W Institute of Physics 2017 Classical and quantum gravity Vol.34 No.4
<P>The second-generation of gravitational-wave detectors are just starting operation, and have already yielding their first detections. Research is now concentrated on how to maximize the scientific potential of gravitational-wave astronomy. To support this effort, we present here design targets for a new generation of detectors, which will be capable of observing compact binary sources with high signal-to-noise ratio throughout the Universe.</P>
Abbott, B. P.,Abbott, R.,Abbott, T. D.,Abernathy, M. R.,Acernese, F.,Ackley, K.,Adams, C.,Adams, T.,Addesso, P.,Adhikari, R. X.,Adya, V. B.,Affeldt, C.,Agathos, M.,Agatsuma, K.,Aggarwal, N.,Aguiar, O. American Physical Society 2016 Physical Review D Vol.94 No.6
<P>We compare GW150914 directly to simulations of coalescing binary black holes in full general relativity, including several performed specifically to reproduce this event. Our calculations go beyond existing semianalytic models, because for all simulations-including sources with two independent, precessing spins - we perform comparisons which account for all the spin-weighted quadrupolar modes, and separately which account for all the quadrupolar and octopolar modes. Consistent with the posterior distributions reported by Abbott et al. [Phys. Rev. Lett. 116, 241102 (2016)] (at the 90% credible level), we find the data are compatible with a wide range of nonprecessing and precessing simulations. Follow-up simulations performed using previously estimated binary parameters most resemble the data, even when all quadrupolar and octopolar modes are included. Comparisons including only the quadrupolar modes constrain the total redshifted mass M-z epsilon [64 M-circle dot - 82 M-circle dot], mass ratio 1/q = m(2)/m(1) epsilon [0.6; 1], and effective aligned spin chi(eff) epsilon [-0.3, 0.2] where chi(eff) = (S-1/m(1)+S-2/m(2)). (L) over cap /M. Including both quadrupolar and octopolar modes, we find the mass ratio is even more tightly constrained. Even accounting for precession, simulations with extreme mass ratios and effective spins are highly inconsistent with the data, at any mass. Several nonprecessing and precessing simulations with similar mass ratio and chi(eff) are consistent with the data. Though correlated, the components' spins (both in magnitude and directions) are not significantly constrained by the data: the data is consistent with simulations with component spin magnitudes a(1,2) up to at least 0.8, with random orientations. Further detailed follow-up calculations are needed to determine if the data contain a weak imprint from transverse (precessing) spins. For nonprecessing binaries, interpolating between simulations, we reconstruct a posterior distribution consistent with previous results. The final black hole's redshifted mass is consistent with M-f,M-z in the range 64.0 M-circle dot - 73.5 M-circle dot and the final black hole's dimensionless spin parameter is consistent with a(f) = 0.62-0.73. As our approach invokes no intermediate approximations to general relativity and can strongly reject binaries whose radiation is inconsistent with the data, our analysis provides a valuable complement to Abbott et al.</P>