Strong Evidence of Anomalous Microwave Emission from the Flux Density Spectrum of M31
| العنوان: | Strong Evidence of Anomalous Microwave Emission from the Flux Density Spectrum of M31 |
|---|---|
| المؤلفون: | Ricardo Genova-Santos, Matteo Murgia, Elia S. Battistelli, Andrea Melis, Federico Radiconi, F. Piacentini, Roberta Paladini, Rafael Rebolo, A. Cruciani, Jose Alberto Rubino-Martin, Federica Guidi, P. de Bernardis, Luca Lamagna, Ettore Carretti, Andrea Tarchi, Gemma Luzzi, Sergio Poppi, Silvia Masi, Valentina Vacca, Alessandro Buzzelli, Paola Castangia, Raimondo Concu, S. Fatigoni, Federica Govoni |
| سنة النشر: | 2019 |
| مصطلحات موضوعية: | 010504 meteorology & atmospheric sciences, Andromeda Galaxy, Infrared, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, galaxies: individual (M31), General Relativity and Quantum Cosmology (gr-qc), Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, General Relativity and Quantum Cosmology, law.invention, Radio telescope, law, 0103 physical sciences, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, Physics, Spectral index, galaxies: ISM, galaxies: photometry, Astronomy and Astrophysics, CMB cold spot, Astrophysics - Astrophysics of Galaxies, Galaxy, Synchrotron, Dipole, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Astrophysics::Earth and Planetary Astrophysics |
| الوصف: | We have observed the Andromeda galaxy, Messier 31 (M31), at 6.7GHz with the Sardinia Radio Telescope. We mapped the radio emission in the C-band, re-analyzed WMAP and Planck maps, as well as other ancillary data, and we have derived an overall integrated flux density spectrum from the radio to the infrared. This allowed us to estimate the emission budget from M31. Integrating over the whole galaxy, we found strong and highly significant evidence for anomalous microwave emission (AME), at the level of (1.45+0.17-0.19)Jy at the peaking frequency of ~25GHz. Decomposing the spectrum into known emission mechanisms such as free-free, synchrotron, thermal dust, and AME arising from electric dipole emission from rapidly rotating dust grains, we found that the overall emission from M31 is dominated, at frequencies below 10GHz, by synchrotron emission with a spectral index of -1.10+0.10-0.08, with subdominant free-free emission. At frequencies >10GHz, AME has a similar intensity to that of synchrotron and free-free emission, overtaking them between 20GHz and 50GHz, whereas thermal dust emission dominates the emission budget at frequencies above 60GHz, as expected. 9 pages, 3 figure, accepted for publication in ApJL |
| وصف الملف: | application/pdf |
| اللغة: | English |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::1396f47e0bb412e8944519aef8a42c5a http://hdl.handle.net/20.500.12386/30218 |
| حقوق: | OPEN |
| رقم الأكسشن: | edsair.doi.dedup.....1396f47e0bb412e8944519aef8a42c5a |
| قاعدة البيانات: | OpenAIRE |
| الوصف غير متاح. |