THE NANOGRAV NINE-YEAR DATA SET: LIMITS ON THE ISOTROPIC STOCHASTIC GRAVITATIONAL WAVE BACKGROUND
| العنوان: | THE NANOGRAV NINE-YEAR DATA SET: LIMITS ON THE ISOTROPIC STOCHASTIC GRAVITATIONAL WAVE BACKGROUND |
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| المؤلفون: | Arzoumanian, Z., Brazier, A., Burke-Spolaor, S., Chamberlin, S.J., Chatterjee, S., Christy, B., Cordes, J.M., Cornish, N.J., Crowter, K., Demorest, P.B., Deng, X., Dolch, T., Ellis, J.A., Ferdman, R.D., Fonseca, E., Garver-Daniels, N., Gonzalez, M.E., Jenet, F., Jones, G., Jones, M.L., Kaspi, V.M., Koop, M., Lam, M.T., Lazio, T.J.W., Levin, L., Lommen, A.N., Lorimer, D.R., Luo, J., Lynch, R.S., Madison, D.R., McLaughlin, M.A., McWilliams, S.T., Mingarelli, C.M.F., Nice, D.J., Palliyaguru, N., Pennucci, T.T., Ransom, S.M., Sampson, L., Sanidas, S.A., Sesana, A., Siemens, X., Simon, J., Stairs, I.H., Stinebring, D.R., Stovall, K., Swiggum, J., Taylor, S.R., Vallisneri, M., van Haasteren, R., Wang, Y., Zhu, W.W. |
| المساهمون: | High Energy Astrophys. & Astropart. Phys (API, FNWI), Arzoumanian, Z, Brazier, A, Burke-Spolaor, S, Chamberlin, S, Chatterjee, S, Christy, B, Cordes, J, Cornish, N, Crowter, K, Demorest, P, Deng, X, Dolch, T, Ellis, J, Ferdman, R, Fonseca, E, Garver-Daniels, N, Gonzalez, M, Jenet, F, Jones, G, Jones, M, Kaspi, V, Koop, M, Lam, M, Lazio, T, Levin, L, Lommen, A, Lorimer, D, Luo, J, Lynch, R, Madison, D, Mclaughlin, M, Mcwilliams, S, Mingarelli, C, Nice, D, Palliyaguru, N, Pennucci, T, Ransom, S, Sampson, L, Sanidas, S, Sesana, A, Siemens, X, Simon, J, Stairs, I, Stinebring, D, Stovall, K, Swiggum, J, Taylor, S, Vallisneri, M, Van Haasteren, R, Wang, Y, Zhu, W |
| المصدر: | NASA Astrophysics Data System Astrophysical Journal, 821(1):13. IOP Publishing Ltd. |
| بيانات النشر: | American Astronomical Society, 2016. |
| سنة النشر: | 2016 |
| مصطلحات موضوعية: | Cosmic microwave background, Planck mass, FOS: Physical sciences, Astrophysics, 01 natural sciences, Power law, Gravitational wave background, symbols.namesake, pulsars: general, 0103 physical sciences, gravitational wave, 010303 astronomy & astrophysics, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, 010308 nuclear & particles physics, Gravitational wave, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, Cosmic string, Amplitude, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), symbols, Astrophysics - High Energy Astrophysical Phenomena, methods: data analysi, Hubble's law |
| الوصف: | We compute upper limits on the nanohertz-frequency isotropic stochastic gravitational wave background (GWB) using the 9-year data release from the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) collaboration. We set upper limits for a GWB from supermassive black hole binaries under power law, broken power law, and free spectral coefficient GW spectrum models. We place a 95\% upper limit on the strain amplitude (at a frequency of yr$^{-1}$) in the power law model of $A_{\rm gw} < 1.5\times 10^{-15}$. For a broken power law model, we place priors on the strain amplitude derived from simulations of Sesana (2013) and McWilliams et al. (2014). We find that the data favor a broken power law to a pure power law with odds ratios of 22 and 2.2 to one for the McWilliams and Sesana prior models, respectively. The McWilliams model is essentially ruled out by the data, and the Sesana model is in tension with the data under the assumption of a pure power law. Using the broken power-law analysis we construct posterior distributions on environmental factors that drive the binary to the GW-driven regime including the stellar mass density for stellar-scattering, mass accretion rate for circumbinary disk interaction, and orbital eccentricity for eccentric binaries, marking the first time that the shape of the GWB spectrum has been used to make astrophysical inferences. We then place the most stringent limits so far on the energy density of relic GWs, $��_\mathrm{gw}(f)\,h^2 < 4.2 \times 10^{-10}$, yielding a limit on the Hubble parameter during inflation of $H_*=1.6\times10^{-2}~m_{Pl}$, where $m_{Pl}$ is the Planck mass. Our limit on the cosmic string GWB, $��_\mathrm{gw}(f)\, h^2 < 2.2 \times 10^{-10}$, translates to a conservative limit of $G�� 21 pages, 12 figures. Please send any comments/questions to justin.ellis18@gmail.com |
| وصف الملف: | application/pdf |
| تدمد: | 1538-4357 0004-637X |
| الوصول الحر: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::7d5b754cff9e07c8929b69f06fae1717Test https://doi.org/10.3847/0004-637x/821/1/13Test |
| حقوق: | OPEN |
| رقم الانضمام: | edsair.doi.dedup.....7d5b754cff9e07c8929b69f06fae1717 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 15384357 0004637X |
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