English
Related papers

Related papers: Secular Decrease and Random Variations of Cassiope…

200 papers

We report about the multi-frequency (1-30 GHz) daily monitoring of the radio flux variability of the three microquasars: SS433, GRS1915+105 and Cyg X-3 during the period from September 2005 to May 2006. 1. We detected clear correlation of…

Astrophysics · Physics 2007-05-23 S. A. Trushkin , N. N. Bursov , T. Kotani , N. A. Nizhelskij , M. Namiki , M. Tsuboi , P. A. Voitsik

We study short-timescale 340 GHz flux-density variability of Sgr A* using ALMA Cycle 3 observations. Careful self-calibration enabled 10 s snapshot imaging with very high effective image-domain SNR, allowing high-cadence monitoring of…

We analyze pulsar fluxes at 1400 MHz ($S_{1400}$) and distances ($d$) extracted from the Parkes Multibeam Survey. Under the assumption that distribution of pulsar luminosities is distance-independent, we find that either (a) pulsar fluxes…

We present Low-Frequency Array (LOFAR) 143.5-MHz radio observations of flaring activity during 2019 May from the X-ray binary Cygnus X-3. Similar to radio observations of previous outbursts from Cygnus X-3, we find that this source was…

We report the results of 20, 6, and 2 cm VLA and 1.5 cm OVRO observations of the optically-selected CfA Seyfert galaxies and the bolometric-flux-limited 12-Micron active galaxy sample. Every object observed was detected at 6 cm. Only 6-8%…

Astrophysics · Physics 2009-10-28 Brian Rush , Matthew A. Malkan , Richard A. Edelson

We present preliminary results of an observation of Cygnus X-1 with INTEGRAL performed on June 7-11 2003. Both spectral and variability properties of the source indicate that Cygnus X-1 was in an intermediate state. As expected during state…

We present an interpretation of the time variability of the $X$-ray flux recently reported from a multi-epoch campaign of $15$ years observations of the supernova remnant Cassiopeia A by {\it Chandra}. We show for the first time…

High Energy Astrophysical Phenomena · Physics 2018-06-27 F. Fraschetti , S. Katsuda , T. Sato , J. R. Jokipii , J. Giacalone

We discuss flaring variability of radio emission of microquasars, measured in monitoring programs with the RATAN-600 radio telescope. We carried out a multi-frequency (1-30 GHz) daily monitoring of the radio flux variability of the…

Astrophysics · Physics 2009-11-13 Sergei A. Trushkin , Nikolaj N. Bursov , Nikolaj A. Nizhelskij

MeV nuclear de-excitation lines serve as a unique tool to study low-energy cosmic rays (CRs), containing both spectral and elemental information of the interacting material. In this paper, we estimated the possible nuclear de-excitation…

High Energy Astrophysical Phenomena · Physics 2023-08-04 Bing Liu , Rui-zhi Yang , Xin-yu He , Felix Aharonian

As part of a European Pulsar Network (EPN) multi-telescope observing campaign, we performed simultaneous multi-frequency observations at 1.4, 4.9 and 8.4 GHz during July 2006 and quasi-simultaneous multi-frequency observations from Decem-…

We use restframe near- and mid-IR data of an isotropically selected sample of quasars and radio galaxies at 1.0 \leq z \leq 1.4, which have been published previously, to study the wavelength-dependent anisotropy of the IR emission. For that…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 S. F. Hoenig , C. Leipski , R. Antonucci , M. Haas

In September 2016, the microquasar Cygnus X-3 underwent a giant radio flare, which was monitored for 6 days with the Medicina Radio Astronomical Station and the Sardinia Radio Telescope. Long observations were performed in order to follow…

We present results of a recent Chandra X-ray Observatory observation of the central compact object (CCO) in the supernova remnant Cassiopeia A. This observation was obtained in an instrumental configuration that combines a high spatial…

High Energy Astrophysical Phenomena · Physics 2009-09-28 G. G. Pavlov , G. J. M. Luna

The microquasar Cygnus X-3 underwent a giant radio flare in April 2017, reaching a maximum flux of $\sim 16.5$ Jy at 8.5 GHz. We present results from a long monitoring campaign carried out with Medicina at 8.5, 18.6 and 24.1 GHz, in…

We present new measurements of the diffuse radio halo emission from the Coma cluster of galaxies at 2.675 GHz and 4.85 GHz using the Effelsberg 100--m telescope. After correction for the contribution from point sources we derive the…

Astrophysics · Physics 2011-07-18 M. Thierbach , U. Klein , R. Wielebinski

We report the discovery of faint very high energy (VHE, E > 100 GeV) gamma-ray emission from the radio galaxy Centaurus A in deep observations performed with the H.E.S.S. experiment. A signal with a statistical significance of 5.0 sigma is…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-14 M. Raue , J. -P. Lenain , F. A. Aharonian , Y. Becherini , C. Boisson , A. -C. Clapson , L. Costamante , L. Gerard , C. Medina , M. de Naurois , M. Punch , F. Rieger , H. Sol , L. Stawarz , A. Zech

We present extensive radio observations of a Type Ic supernova, ASASSN-16fp. Our data represents the lowest frequency observations of the SN beyond 1000 days with a frequency range of $0.33-25$ GHz and a temporal range of $\sim$ 8 to 1136…

High Energy Astrophysical Phenomena · Physics 2021-07-14 Nayana A. J. , Poonam Chandra

We report Chandra ACIS and quasi-simultaneous RXTE observations of the nearby, powerful radio galaxy Cygnus A, with the present paper focusing on the properties of the active nucleus. In the Chandra observation, the hard (> a few keV) X-ray…

We present a study of the CCSN rate in nuclei A and B1 of the luminous infrared galaxy Arp299, based on 11 years of Very Large Array monitoring of their radio emission at 8.4 GHz. Significant variations in the nuclear radio flux density can…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Cristina Romero-Canizales , Seppo Mattila , Antxon Alberdi , Miguel Angel Perez-Torres , Erkki Kankare , Stuart D. Ryder

We present Spitzer IRAC images, along with representative 5.27 to 38.5 micron IRS spectra of the Cassiopeia A supernova remnant. We find that various IRAC channels are each most sensitive to a different spectral and physical component.…

Astrophysics · Physics 2008-11-26 J. A. Ennis , L. Rudnick , W. T. Reach , J. D. Smith , J. Rho , T. DeLaney , H. Gomez , T. Kozasa