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Author |
Villanueva-Domingo, P.; Villaescusa-Navarro, F. |
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Title  |
Removing Astrophysics in 21 cm Maps with Neural Networks |
Type |
Journal Article |
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Year |
2021 |
Publication |
Astrophysical Journal |
Abbreviated Journal |
Astrophys. J. |
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Volume |
907 |
Issue |
1 |
Pages |
44 - 14pp |
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Keywords |
Cosmology; Cold dark matter; Dark matter; Dark matter distribution; H I line emission; Intergalactic medium; Cosmological evolution; Convolutional neural networks; Large-scale structure of the universe |
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Abstract |
Measuring temperature fluctuations in the 21 cm signal from the epoch of reionization and the cosmic dawn is one of the most promising ways to study the universe at high redshifts. Unfortunately, the 21 cm signal is affected by both cosmology and astrophysics processes in a nontrivial manner. We run a suite of 1000 numerical simulations with different values of the main astrophysical parameters. From these simulations we produce tens of thousands of 21 cm maps at redshifts 10 <= z <= 20. We train a convolutional neural network to remove the effects of astrophysics from the 21 cm maps and output maps of the underlying matter field. We show that our model is able to generate 2D matter fields not only that resemble the true ones visually but whose statistical properties agree with the true ones within a few percent down to scales 2 Mpc(-1). We demonstrate that our neural network retains astrophysical information that can be used to constrain the value of the astrophysical parameters. Finally, we use saliency maps to try to understand which features of the 21 cm maps the network is using in order to determine the value of the astrophysical parameters. |
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Address |
[Villanueva-Domingo, Pablo] Univ Valencia, Inst Fis Corpuscular IFIC, CSIC, Apartado Correos 22085, E-46071 Valencia, Spain, Email: Pablo.Villanueva@ific.uv.es; |
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Iop Publishing Ltd |
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English |
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0004-637x |
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WOS:000612333400001 |
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no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
4698 |
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Author |
HAWC Collaboration (Albert, A. et al); Salesa Greus, F. |
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Title |
Probing the Sea of Cosmic Rays by Measuring Gamma-Ray Emission from Passive Giant Molecular Clouds with HAWC |
Type |
Journal Article |
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Year |
2021 |
Publication |
Astrophysical Journal |
Abbreviated Journal |
Astrophys. J. |
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Volume |
914 |
Issue |
2 |
Pages |
106 - 14pp |
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Abstract |
The study of high-energy gamma rays from passive giant molecular clouds (GMCs) in our Galaxy is an indirect way to characterize and probe the paradigm of the “sea” of cosmic rays in distant parts of the Galaxy. By using data from the High Altitude Water Cerenkov (HAWC) Observatory, we measure the gamma-ray flux above 1 TeV of a set of these clouds to test the paradigm. We selected high galactic latitude clouds that are in HAWC's field of view and that are within 1 kpc distance from the Sun. We find no significant excess emission in the cloud regions, nor when we perform a stacked log-likelihood analysis of GMCs. Using a Bayesian approach, we calculate 95% credible interval upper limits of the gamma-ray flux and estimate limits on the cosmic-ray energy density of these regions. These are the first limits to constrain gamma-ray emission in the multi-TeV energy range (>1 TeV) using passive high galactic latitude GMCs. Assuming that the main gamma-ray production mechanism is due to proton-proton interaction, the upper limits are consistent with a cosmic-ray flux and energy density similar to that measured at Earth. |
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Address |
[Albert, A.; Dingus, B. L.; Durocher, M.; Harding, J. P.; Malone, K.] Los Alamos Natl Lab, Phys Div, Los Alamos, NM 87545 USA, Email: hgayala@psu.edu |
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Iop Publishing Ltd |
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English |
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0004-637x |
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WOS:000663912700001 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
4858 |
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Author |
HAWC Collaboration (Albert, A. et al); Salesa Greus, F. |
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Title |
Probing the Extragalactic Mid-infrared Background with HAWC |
Type |
Journal Article |
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Year |
2022 |
Publication |
Astrophysical Journal |
Abbreviated Journal |
Astrophys. J. |
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Volume |
933 |
Issue |
2 |
Pages |
223 - 8pp |
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Abstract |
The extragalactic background light (EBL) contains all the radiation emitted by nuclear and accretion processes in stars and compact objects since the epoch of recombination. Measuring the EBL density directly is challenging, especially in the near-to-far-infrared wave band, mainly due to the zodiacal light foreground. Instead, gamma-ray astronomy offers the possibility to indirectly set limits on the EBL by studying the effects of gamma-ray absorption in the very high energy (VHE: >100 GeV) spectra of distant blazars. The High Altitude Water Cherenkov Gamma Ray Observatory (HAWC) is one of the few instruments sensitive to gamma rays with energies above 10 TeV. This offers the opportunity to probe the EBL in the near/mid-IR region: lambda = 1-100 μm. In this study, we fit physically motivated emission models to Fermi-LAT gigaelectronvolt data to extrapolate the intrinsic teraelectronvolt spectra of blazars. We then simulate a large number of absorbed spectra for different randomly generated EBL model shapes and calculate Bayesian credible bands in the EBL intensity space by comparing and testing the agreement between the absorbed spectra and HAWC extragalactic observations of two blazars. The resulting bands are in agreement with current EBL lower and upper limits, showing a downward trend toward higher wavelength values lambda > 10 μm also observed in previous measurements. |
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Address |
[Albert, A.; Durocher, M.; Harding, J. P.; Malone, K.] Los Alamos Natl Lab, Phys Div, Los Alamos, NM USA, Email: mkf5479@psu.edu |
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IOP Publishing Ltd |
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English |
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0004-637x |
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Notes |
WOS:000826698600001 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
5295 |
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Author |
de Putter, R.; Mena, O.; Giusarma, E.; Ho, S.; Cuesta, A.; Seo, H.J.; Ross, A.J.; White, M.; Bizyaev, D.; Brewington, H.; Kirkby, D.; Malanushenko, E.; Malanushenko, V.; Oravetz, D.; Pan, K.K.; Percival, W.J.; Ross, N.P.; Schneider, D.P.; Shelden, A.; Simmons, A.; Snedden, S. |
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Title |
New Neutrino Mass Bounds from SDSS-III Data Release 8 Photometric Luminous Galaxies |
Type |
Journal Article |
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Year |
2012 |
Publication |
Astrophysical Journal |
Abbreviated Journal |
Astrophys. J. |
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Volume |
761 |
Issue |
1 |
Pages |
12 - 12pp |
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Keywords |
cosmological parameters; cosmology: observations; large-scale structure of universe |
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Abstract |
We present neutrino mass bounds using 900,000 luminous galaxies with photometric redshifts measured from Sloan Digital Sky Survey III Data Release 8. The galaxies have photometric redshifts between z = 0.45 and z = 0.65 and cover 10,000 deg(2), thus probing a volume of 3 h(-3) Gpc(3) and enabling tight constraints to be derived on the amount of dark matter in the form of massive neutrinos. A new bound on the sum of neutrino masses Sigma m nu < 0.27 eV, at the 95% confidence level (CL), is obtained after combining our sample of galaxies, which we call “CMASS,” with Wilkinson Microwave Anisotropy Probe (WMAP) seven-year cosmic microwave background data and the most recent measurement of the Hubble parameter from the Hubble Space Telescope (HST). This constraint is obtained with a conservative multipole range of 30 < l < 200 in order to minimize nonlinearities, and a free bias parameter in each of the four redshift bins. We study the impact of assuming this linear galaxy bias model using mock catalogs and find that this model causes a small (similar to 1 sigma-1.5 sigma) bias in Omega(DM)h(2). For this reason, we also quote neutrino bounds based on a conservative galaxy bias model containing additional, shot-noise-like free parameters. In this conservative case, the bounds are significantly weakened, e. g., Sigma m(nu) < 0.38 eV (95% CL) for WMAP+HST+CMASS (l(max) = 200). We also study the dependence of the neutrino bound on the multipole range (l(max) = 150 versus l(max) = 200) and on which combination of data sets is included as a prior. The addition of supernova and/or baryon acoustic oscillation data does not significantly improve the neutrino mass bound once the HST prior is included. A companion paper describes the construction of the angular power spectra in detail and derives constraints on a general cosmological model, including the dark energy equation of state w and the spatial curvature Omega(K), while a second companion paper presents a measurement of the scale of baryon acoustic oscillations from the same data set. All three works are based on the catalog by Ross et al. |
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Address |
[de Putter, Roland] Univ Barcelona, ICC, IEEC UB, E-08028 Barcelona, Spain |
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Iop Publishing Ltd |
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English |
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0004-637x |
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Notes |
WOS:000311748800012 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
1262 |
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Author |
Reichardt, C.L.; de Putter, R.; Zahn, O.; Hou, Z. |
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Title |
New limits on early dark energy from the South Pole telescope |
Type |
Journal Article |
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Year |
2012 |
Publication |
Astrophysical Journal Letters |
Abbreviated Journal |
Astrophys. J. Lett. |
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Volume |
749 |
Issue |
1 |
Pages |
L9 - 5pp |
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Keywords |
cosmic background radiation; dark energy; early universe |
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Abstract |
We present new limits on early dark energy (EDE) from the cosmic microwave background (CMB) using data from the Wilkinson Microwave Anisotropy Probe (WMAP) satellite on large angular scales and South Pole Telescope on small angular scales. We find a strong upper limit on the EDE density of Omega(e) < 0.018 at 95% confidence, a factor of three improvement over WMAP data alone. We show that adding lower-redshift probes of the expansion rate to the CMB data improves constraints on the dark energy equation of state, but not the EDE density. We also explain how small-scale CMB temperature anisotropy constrains EDE. |
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Address |
[Reichardt, C. L.; Zahn, O.] Univ Calif Berkeley, Dept Phys, Berkeley Ctr Cosmol Phys, Berkeley, CA 94720 USA, Email: cr@bolo.berkeley.edu |
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Publisher |
Iop Publishing Ltd |
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English |
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ISSN |
2041-8205 |
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Notes |
WOS:000302143100009 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
962 |
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Author |
ANTARES Collaboration (Adrian-Martinez, S. et al); Barrios-Marti, J.; Hernandez-Rey, J.J.; Sanchez-Losa, A.; Tönnis, C.; Zornoza, J.D.; Zuñiga, J. |
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Title |
Murchison Widefield Array Limits on Radio Emission from ANTARES Neutrino Events |
Type |
Journal Article |
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Year |
2016 |
Publication |
Astrophysical Journal Letters |
Abbreviated Journal |
Astrophys. J. Lett. |
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Volume |
820 |
Issue |
2 |
Pages |
L24 - 7pp |
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Keywords |
neutrinos; radio continuum: general |
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Abstract |
We present a search, using the Murchison Widefield Array (MWA), for electromagnetic (EM) counterparts to two candidate high-energy neutrino events detected by the ANTARES neutrino telescope in 2013 November and 2014 March. These events were selected by ANTARES because they are consistent, within 0 degrees.4, with the locations of galaxies within 20 Mpc of Earth. Using MWA archival data at frequencies between 118 and 182 MHz, taken similar to 20. days prior to, at the same time as, and up to a year after the neutrino triggers, we look for transient or strongly variable radio sources that are consistent with the neutrino positions. No such counterparts are detected, and we set a 5 sigma upper limit for low-frequency radio emission of similar to 10(37) erg s(-1) for progenitors at 20 Mpc. If the neutrino sources are instead not in nearby galaxies, but originate in binary neutron star coalescences, our limits place the progenitors at z greater than or similar to 0.2. While it is possible, due to the high background from atmospheric neutrinos, that neither event is astrophysical, the MWA observations are nevertheless among the first to follow up neutrino candidates in the radio, and illustrate the promise of wide-field instruments like MWA for detecting EM counterparts to such events. |
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Address |
[Croft, S.; Zheng, W.] Univ Calif Berkeley, Dept Astron, 501 Campbell Hall 3411, Berkeley, CA 94720 USA |
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Iop Publishing Ltd |
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English |
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2041-8205 |
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Notes |
WOS:000373085300002 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
2613 |
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Author |
AMON Team, HAWC and IceCube Collaborations (Ayala Solares, H.A. et al); Salesa Greus, F. |
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Title |
Multimessenger Gamma-Ray and Neutrino Coincidence Alerts Using HAWC and IceCube Subthreshold Data |
Type |
Journal Article |
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Year |
2021 |
Publication |
Astrophysical Journal |
Abbreviated Journal |
Astrophys. J. |
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Volume |
906 |
Issue |
1 |
Pages |
63 - 10pp |
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Abstract |
The High Altitude Water Cerenkov (HAWC) and IceCube observatories, through the Astrophysical Multimessenger Observatory Network (AMON) framework, have developed a multimessenger joint search for extragalactic astrophysical sources. This analysis looks for sources that emit both cosmic neutrinos and gamma rays that are produced in photohadronic or hadronic interactions. The AMON system is running continuously, receiving subthreshold data (i.e., data that are not suited on their own to do astrophysical searches) from HAWC and IceCube, and combining them in real time. Here we present the analysis algorithm, as well as results from archival data collected between 2015 June and 2018 August, with a total live time of 3.0 yr. During this period we found two coincident events that have a false-alarm rate (FAR) of <1 coincidence yr(-1), consistent with the background expectations. The real-time implementation of the analysis in the AMON system began on 2019 November 20 and issues alerts to the community through the Gamma-ray Coordinates Network with an FAR threshold of <4 coincidences yr(-1). |
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Address |
[Solares, H. A. Ayala; Coutu, S.; DeLaunay, J. J.; Fox, D. B.; Gregoire, T.; Keivani, A.; Krauss, F.; Mostafa, M.; Murase, K.; Turley, C. F.; Anderson, T.; Cowen, D. F.; Dunkman, M.; Eller, P.; Fienberg, A.; Huang, F.; Kheirandish, A.; Lanfranchi, J. L.; Li, Y.; Pankova, D. V.; Weiss, M. J.] Penn State Univ, Dept Phys, University Pk, PA 16802 USA, Email: hgayala@psu.edu |
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Iop Publishing Ltd |
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English |
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0004-637x |
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WOS:000605929400001 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
4679 |
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Author |
LIGO Sci, Virgo, ANTARES and other Collaborations (Abbott, B.P. et al); Barrios-Marti, J.; Coleiro, A.; Hernandez-Rey, J.J.; Illuminati, G.; Lotze, M.; Tönnis, C.; Zornoza, J.D.; Zuñiga, J. |
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Title |
Multi-messenger Observations of a Binary Neutron Star Merger |
Type |
Journal Article |
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Year |
2017 |
Publication |
Astrophysical Journal Letters |
Abbreviated Journal |
Astrophys. J. Lett. |
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Volume |
848 |
Issue |
2 |
Pages |
L12 - 59pp |
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Keywords |
gravitational waves; stars: neutron |
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Abstract |
On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of similar to 1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg(2) at a luminosity distance of 40(-8)(+8) Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 M-circle dot. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at similar to 40 Mpc) less than 11 hours after the merger by the One-Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over similar to 10 days. Following early non-detections, X-ray and radio emission were discovered at the transient's position similar to 9 and similar to 16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta. |
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[Abbott, B. P.; Abbott, R.; Adhikari, R. X.; Ananyeva, A.; Anderson, S. B.; Appert, S.; Arai, K.; Araya, M. C.; Barayoga, J. C.; Barish, B. C.; Berger, B. K.; Billingsley, G.; Biscans, S.; Blackburn, J. K.; Blair, C. D.; Brooks, A. F.; Brunett, S.; Cahillane, C.; Callister, T. A.; Cepeda, C. B.; Coughlin, M. W.; Couvares, P.; Coyne, D. C.; Ehrens, P.; Eichholz, J.; Etzel, T.; Feicht, J.; Fries, E. M.; Gossan, S. E.; Gushwa, K. E.; Gustafson, E. K.; Heptonstall, A. W.; Isi, M.; Kamai, B.; Kanner, J. B.; Kondrashov, V.; Korth, W. Z.; Kozak, D. B.; Lazzarini, A.; Markowitz, A.; Maros, E.; Massinger, T. J.; Matichard, F.; McIntyre, G.; McIver, J.; Meshkov, S.; Nevin, L.; Pedraza, M.; Perreca, A.; Price, L. R.; Quintero, E. A.; Reitze, D. H.; Robertson, N. A.; Rollins, J. G.; Sachdev, S.; Sanchez, E. J.; Sanchez, L. E.; Schmidt, P.; Smith, R. J. E.; Taylor, R.; Torrie, C. I.; Tso, R.; Urban, A. L.; Vajente, G.; Vass, S.; Venugopalan, G.; Verkindt, D.; Vetro, F.; Wade, A. R.; Wallace, L.; Weinstein, A. J.; Whitcomb, S. E.; Williams, R. D.; Willke, B.; Wipf, C. C.; Xiao, S.; Yamamoto, H.; Zhang, L.; Zucker, M. E.; Zweizig, J.] CALTECH, LIGO, Pasadena, CA 91125 USA |
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Iop Publishing Ltd |
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English |
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2041-8205 |
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Notes |
WOS:000413211000001 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
3354 |
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Author |
Kiss, G.G. et al; Tarifeño-Saldivia, A.; Tain, J.L.; Agramunt, J.; Algora, A.; Domingo-Pardo, C.; Morales, A.I.; Nacher, E.; Rubio, B.; Tolosa, A. |
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Title |
Measuring the beta-decay Properties of Neutron-rich Exotic Pm, Sm, Eu, and Gd Isotopes to Constrain the Nucleosynthesis Yields in the Rare-earth Region |
Type |
Journal Article |
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Year |
2022 |
Publication |
Astrophysical Journal |
Abbreviated Journal |
Astrophys. J. |
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Volume |
936 |
Issue |
2 |
Pages |
107 - 18pp |
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Abstract |
The beta-delayed neutron-emission probabilities of 28 exotic neutron-rich isotopes of Pm, Sm, Eu, and Gd were measured for the first time at RIKEN Nishina Center using the Advanced Implantation Detector Array (AIDA) and the BRIKEN neutron detector array. The existing beta-decay half-life (T (1/2)) database was significantly increased toward more neutron-rich isotopes, and uncertainties for previously measured values were decreased. The new data not only constrain the theoretical predictions of half-lives and beta-delayed neutron-emission probabilities, but also allow for probing the mechanisms of formation of the high-mass wing of the rare-earth peak located at A approximate to 160 in the r-process abundance distribution through astrophysical reaction network calculations. An uncertainty quantification of the calculated abundance patterns with the new data shows a reduction of the uncertainty in the rare-earth peak region. The newly introduced variance-based sensitivity analysis method offers valuable insight into the influence of important nuclear physics inputs on the calculated abundance patterns. The analysis has identified the half-lives of Sm-168 and of several gadolinium isotopes as some of the key variables among the current experimental data to understand the remaining abundance uncertainty at A = 167-172. |
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Address |
[Kiss, G. G.; Vitez-Sveiczer, A.; Algora, A.; Szegedi, T. N.] Inst Nucl Res ATOMKI, Bem Ter 18-c, H-4026 Debrecen, Hungary, Email: ggkiss@atomki.hu; |
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IOP Publishing Ltd |
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English |
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0004-637x |
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WOS:000850804600001 |
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no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
5353 |
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Author |
HAWC Collaboration (Albert, A. et al); Salesa Greus, F. |
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Title |
Long-term Spectra of the Blazars Mrk 421 and Mrk 501 at TeV Energies Seen by HAWC |
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Journal Article |
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2022 |
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Astrophysical Journal |
Abbreviated Journal |
Astrophys. J. |
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929 |
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2 |
Pages |
125 - 12pp |
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The High Altitude Water Cherenkov (HAWC) Gamma-Ray Observatory surveys the very high-energy sky in the 300 GeV to >100 TeV energy range. HAWC has detected two blazars above 11 sigma, Markarian 421 (Mrk 421) and Markarian 501 (Mrk 501). The observations are comprised of data taken in the period between 2015 June and 2018 July, resulting in similar to 1038 days of exposure. In this work, we report the time-averaged spectral analyses for both sources, above 0.5 TeV. Taking into account the flux attenuation due to the extragalactic background light, the intrinsic spectrum of Mrk 421 is described by a power law with an exponential energy cutoff with index alpha = 2.26 +/- (0.12)(stat)((+0.17)(-0.2))(sys) and energy cutoff E-c = 5.1 +/- (1.6)(stat)((+1.4)(-2.5))(sys) TeV, while the intrinsic spectrum of Mrk 501 is better described by a simple power law with index alpha = 2.61 +/- (0.11)(stat)((+)(0.01)(-0.07))(sys). The maximum energies at which the Mrk 421 and Mrk 501 signals are detected are 9 and 12 TeV, respectively. This makes these some of the highest energy detections to date for spectra averaged over years-long timescales. Since the observation of gamma radiation from blazars provides information about the physical processes that take place in their relativistic jets, it is important to study the broadband spectral energy distributions (SEDs) of these objects. For this purpose, contemporaneous data in the gamma-ray band to the X-ray range, and literature data in the radio to UV range, were used to build time-averaged SEDs that were modeled within a synchrotron-self Compton leptonic scenario. |
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[Albert, A.; Durocher, M.; Harding, J. P.] Los Alamos Natl Lab, Phys Div, Los Alamos, NM 87545 USA, Email: alberto@inaoep.mx; |
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IOP Publishing Ltd |
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English |
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0004-637x |
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Notes |
WOS:000785694100001 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
5209 |
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