Zobrazeno 1 - 10
of 516
pro vyhledávání: '"SANNA, ANDREA"'
Autor:
Singh, Akshay, Sanna, Andrea, Bhattacharyya, Sudip, Chakraborty, Sudiip, Jangle, Sarita, Katoch, Tlak, Antia, H. M., Bijewar, Nitinkumar
IGR J17591--2342, a transient accretion-powered millisecond X-ray pulsar, was discovered during its 2018 outburst. Here, we present a timing and spectral analysis of the source using {\it AstroSat} data of the same outburst. From the timing analysis,
Externí odkaz:
http://arxiv.org/abs/2412.11143
Autor:
Ng, Mason, Hare, Jeremy, Jaisawal, Gaurava K., Malacaria, Christian, Markwardt, Craig B., Sanna, Andrea
Publikováno v:
Res. Notes AAS 8 292 (2024)
We report on follow-up observations of the recently discovered transient by the Einstein Probe, EP240709A, with the Neutron star Interior Composition Explorer (NICER). We also incorporated archival multiwavelength survey data from the Neil Gehrels Sw
Externí odkaz:
http://arxiv.org/abs/2411.18718
Autor:
Partington, Ethan R., Cackett, Edward M., Edelson, Rick, Horne, Keith, Gelbord, Jonathan, Kara, Erin, Malacaria, Christian, Miller, Jake A., Steiner, James F., Sanna, Andrea
The Seyfert 1 AGN Fairall 9 was targeted by NICER, Swift, and ground-based observatories for a $\sim$1000-day long reverberation mapping campaign. The following analysis of NICER spectra taken at a two-day cadence provides new insights into the struc
Externí odkaz:
http://arxiv.org/abs/2410.21432
Using the Functional Renormalization Group approach we construct effective quantum spacetime geometries by self-consistently deforming the classical Schwarzschild-de Sitter black-hole solution. This involves studying how quantum corrections, driven b
Externí odkaz:
http://arxiv.org/abs/2410.16866
We present exact solutions for the cosmological embedding of a broad class of non-singular black holes, demonstrating that these objects exhibit an apparent horizon. The evolution of the latter is analyzed as a function of the cosmological redshift $
Externí odkaz:
http://arxiv.org/abs/2410.10459
Autor:
Illiano, Giulia, Papitto, Alessandro, Marino, Alessio, Strohmayer, Tod E., Sanna, Andrea, Di Salvo, Tiziana, La Placa, Riccardo, Ambrosino, Filippo, Zanon, Arianna Miraval, Zelati, Francesco Coti, Ballocco, Caterina, Malacaria, Christian, Ghedina, Adriano, Cecconi, Massimo, Gonzales, Manuel, Leone, Franco
Publikováno v:
A&A 691, A189 (2024)
We present a comprehensive study of the X-ray spectral properties of the accreting millisecond pulsar IGR J17498$-$2921 during its 2023 outburst. Similar to other accreting millisecond pulsars, the broad-band spectral emission observed quasi-simultan
Externí odkaz:
http://arxiv.org/abs/2408.06895
Autor:
Papitto, Alessandro, Di Marco, Alessandro, Poutanen, Juri, Salmi, Tuomo, Illiano, Giulia, La Monaca, Fabio, Ambrosino, Filippo, Bobrikova, Anna, Baglio, Maria Cristina, Ballocco, Caterina, Burderi, Luciano, Campana, Sergio, Zelati, Francesco Coti, Di Salvo, Tiziana, La Placa, Riccardo, Loktev, Vladislav, Long, Sinan, Malacaria, Christian, Zanon, Arianna Miraval, Ng, Mason, Pilia, Maura, Sanna, Andrea, Stella, Luigi, Strohmayer, Tod, Zane, Silvia
We report on the discovery of polarized X-ray emission from an accreting millisecond pulsar. During a 10-day-long coverage of the February 2024 outburst of SRGA J144459.2-604207, the Imaging X-ray Polarimetry Explorer (IXPE) detected an average polar
Externí odkaz:
http://arxiv.org/abs/2408.00608
We show that, in the framework of Einstein-scalar gravity, the de Sitter (dS) spacetime can be nucleated out of the anti de Sitter (AdS) one. This is done by using a scalar lump solution, which has an $\text{AdS}_4$ spacetime in the core, allows for
Externí odkaz:
http://arxiv.org/abs/2407.10469
Autor:
Ulgiati, Alberto, Vincentelli, Federico Maria, Casella, Piergiorgio, Veledina, Alexandra, Maccarone, Thomas, Russell, David, Uttley, Phil, Ambrosino, Filippo, Baglio, Maria Cristina, Imbrogno, Matteo, Melandri, Andrea, Motta, Sara Elisa, O'Brien, Kiran, Sanna, Andrea, Shahbaz, Tariq, Altamirano, Diego, Fender, Rob, Maitra, Dipankar, Malzac, Julien
Publikováno v:
A&A 690, A239 (2024)
We report on two epochs of simultaneous near-infrared (IR) and X-ray observations with a sub-second time resolution of the low mass X-ray binary black hole candidate Swift J1753.5--0127 during its long 2005--2016 outburst. Data were collected strictl
Externí odkaz:
http://arxiv.org/abs/2407.00195
We investigate the cosmological coupling of spherical, local astrophysical systems. We derive a general formula quantifying the cosmological coupling of the Misner-Sharp mass of these objects. We show that, in the weak-field limit, the cosmological c
Externí odkaz:
http://arxiv.org/abs/2406.06091