papers

Publications (186)

astro-ph.HE2015

First NuSTAR Observations of Mrk 501 within a Radio to TeV Multi-Instrument Campaign

A. Furniss, K. Noda, S. Boggs +273

We report on simultaneous broadband observations of the TeV-emitting blazar Markarian 501 between 1 April and 10 August 2013, including the first detailed characterization of the s…

astro-ph.IM2011

Recovering Swift-XRT energy resolution through CCD charge trap mapping

C. Pagani, A. P. Beardmore, A. F. Abbey +13

The X-ray telescope on board the Swift satellite for gamma-ray burst astronomy has been exposed to the radiation of the space environment since launch in November 2004. Radiation c…

astro-ph.IM2015

Cherenkov Telescope Array Data Management

G. Lamanna, L. A. Antonelli, J. L. Contreras +37

Very High Energy gamma-ray astronomy with the Cherenkov Telescope Array (CTA) is evolving towards the model of a public observatory. Handling, processing and archiving the large am…

astro-ph.HE2022

The lively accretion disk in NGC 2992. II. The 2019/2021 X-ray monitoring campaigns

R. Middei, A. Marinucci, V. Braito +8

We report on the short and long term X-ray properties of the bright nearby Seyfert 2 galaxy NGC 2992, which was extensively observed with Swift, XMM-Newton and NuSTAR. Swift target…

astro-ph.HE2018

The Bright -ray Flare of 3C 279 in June 2015: AGILE Detection and Multifrequency Follow-up Observations

C. Pittori, F. Lucarelli, F. Verrecchia +44

We report the AGILE detection and the results of the multifrequency follow-up observations of a bright -ray flare of the blazar 3C 279 in June 2015. We use AGILE-GRID and Fermi…

astro-ph.HE2021

Study of the variable broadband emission of Markarian 501 during the most extreme Swift X-ray activity

MAGIC Collaboration, V. A. Acciari, S. Ansoldi +185

Mrk501 is a very high-energy (VHE) gamma-ray blazar located at z=0.034. During a period of two weeks in July 2014, the highest X-ray activity of Mrk501 was observed in ~14 years of…

astro-ph.HE2021

Investigation of the correlation patterns and the Compton dominance variability of Mrk 421 in 2017

MAGIC Collaboration, V. A. Acciari, S. Ansoldi +284

We present a detailed characterisation and theoretical interpretation of the broadband emission of the paradigmatic TeV blazar Mrk 421, with special focus on the multi-band flux co…

astro-ph2007

GRB 070311: a direct link between the prompt emission and the afterglow

C. Guidorzi, S. D. Vergani, S. Sazonov +30

We present prompt gamma-ray, early NIR/optical, late optical and X-ray observations of the peculiar GRB 070311 discovered by INTEGRAL, in order to gain clues on the mechanisms resp…

astro-ph.IM2018

Science with the Cherenkov Telescope Array

The Cherenkov Telescope Array Consortium, :, B. S. Acharya +580

The Cherenkov Telescope Array, CTA, will be the major global observatory for very high energy gamma-ray astronomy over the next decade and beyond. The scientific potential of CTA i…

astro-ph2007

Swift detection of all previously undetected blazars in a micro-wave flux-limited sample of WMAP foreground sources

P. Giommi, M. Capalbi, E. Cavazzuti +19

Almost the totality of the bright foreground sources in the WMAP CMB maps are blazars, a class of sources that show usually also X-ray emission. However, 23 objects in a flux-limit…

astro-ph.HE2023

The geometry of the hot corona in MCG-05-23-16 constrained by X-ray polarimetry

D. Tagliacozzo, A. Marinucci, F. Ursini +105

We report on the second observation of the radio-quiet active galactic nucleus (AGN) MCG-05-23-16 performed with the Imaging X-ray Polarimetry Explorer (IXPE). The observation star…

astro-ph2007

Swift GRBs: the early afterglow spectral energy distribution

G. Tagliaferri, D. Malesani, S. D. Vergani +16

We present the first results of a program to systematically study the optical-to-X-ray spectral energy distribution (SED) of Swift GRB afterglows with known redshift. The goal is t…

astro-ph2003

Log-parabolic spectra and particle acceleration in the BL Lac object Mkn 421: spectral analysis of the complete BeppoSAX wide band X-ray data set

E. Massaro, M. Perri, P. Giommi +1

We report the results of a new analysis of 13 wide band BeppoSAX observations of the BL Lac object Mkn 421. The data from LECS, MECS and PDS, covering an energy interval from 0.1 t…

astro-ph2008

Roma-BZCAT: A multifrequency catalogue of Blazars

E. Massaro, P. Giommi, C. Leto +5

We present a new catalogue of blazars based on multi-frequency surveys and on an extensive review of the literature. Blazars are classified as BL Lacertae objects, as flat spectrum…

astro-ph2007

Blazar surveys with WMAP and Swift

P. Giommi, M. Capalbi, E. Cavazzuti +7

We present the preliminary results from two new surveys of blazars that have direct implications on the GLAST detection of extragalactic sources from two different perspectives: mi…

astro-ph.HE2010

The afterglow and host galaxy of GRB 090205: evidence for a Ly-alpha emitter at z=4.65

P. D'Avanzo, M. Perri, D. Fugazza +17

Gamma-ray bursts have been proved to be detectable up to distances much larger than any other astrophysical object, providing the most effective way, complementary to ordinary surv…

astro-ph2002

Parameter Correlations and Cosmological Properties of BL Lac Objects

P. Giommi, P. Padovani, M. Perri +2

Using three complete, radio flux limited, blazar samples we compare the LogN-LogS and the preliminary radio luminosity function of the general population of BL Lacs to those of the…

astro-ph.HE2015

Multiwavelength Evidence for Quasi-periodic Modulation in the Gamma-ray Blazar PG 1553+113

The Fermi LAT collaboration, M. Ackermann, M. Ajello +139

We report for the first time a gamma-ray and multi-wavelength nearly-periodic oscillation in an active galactic nucleus. Using the Fermi Large Area Telescope (LAT) we have discover…

astro-ph.CO2009

Multiwavelength observations of 3C 454.3 II. The AGILE 2007 December campaign

I. Donnarumma, G. Pucella, V. Vittorini +75

We report on the second AGILE multiwavelength campaign of the blazar 3C 454.3 during the first half of December 2007. This campaign involved AGILE, Spitzer, Swift,Suzaku,the WEBT c…

astro-ph.HE2023

Simultaneous and panchromatic observations of the Fast Radio Burst FRB 20180916B

M. Trudu, M. Pilia, L. Nicastro +47

Aims. Fast Radio Bursts are bright radio transients whose origin has not yet explained. The search for a multi-wavelength counterpart of those events can put a tight constrain on t…

astro-ph2005

An unexpectedly rapid decline in the X-ray afterglow emission of long gamma-ray bursts

G. Tagliaferri, M. Goad, G. Chincarini +32

Long gamma-ray bursts (GRBs) are commonly accepted to originate in the explosion of particularly massive stars, which gives rise to a highly relativistic jet. Internal inhomogeneit…

astro-ph2007

An online repository of Swift/XRT light curves of GRBs

P. A. Evans, A. P. Beardmore, K. L. Page +12

Context. Swift data are revolutionising our understanding of Gamma Ray Bursts. Since bursts fade rapidly, it is desirable to create and disseminate accurate light curves rapidly. A…

astro-ph.HE2020

Swift Multiwavelength Follow-up of LVC S200224ca and the Implications for Binary Black Hole Mergers

N. J. Klingler, A. Lien, S. R. Oates +41

On 2020 February 24, during their third observing run ("O3"), the Laser Interferometer Gravitational-wave Observatory and Virgo Collaboration (LVC) detected S200224ca: a candidate…

astro-ph2008

AGILE and Swift simultaneous observations of the blazar S50716+714 during the bright flare of October 2007

P. Giommi, S. Colafrancesco, S. Cutini +15

We present the results of a series of optical, UV, X-ray and gamma-ray observations of the BL Lac object S50716+714 carried out by the Swift and AGILE satellites in late 2007 when…

astro-ph.HE2024

X-ray polarization measurement of the gold standard of radio-quiet active galactic nuclei : NGC 1068

F. Marin, A. Marinucci, M. Laurenti +102

We used the Imaging X-ray Polarimetry Explorer (IXPE) satellite to measure, for the first time, the 2-8 keV polarization of NGC 1068. We pointed IXPE for a net exposure time of 1.1…

astro-ph.HE2015

The 2009 multiwavelength campaign on Mrk 421: Variability and correlation studies

MAGIC Collaboration, J. Aleksić, S. Ansoldi +270

We performed a 4.5-month multi-instrument campaign (from radio to VHE gamma rays) on Mrk421 between January 2009 and June 2009, which included VLBA, F-GAMMA, GASP-WEBT, Swift, RXTE…

astro-ph.HE2023

First characterization of the emission behavior of Mrk421 from radio to VHE gamma rays with simultaneous X-ray polarization measurements

S. Abe, J. Abhir, V. A. Acciari +250

We perform the first broadband study of Mrk421 from radio to TeV gamma rays with simultaneous measurements of the X-ray polarization from IXPE. The data were collected within an ex…

astro-ph2005

The Giant X-ray Flare of GRB 050502B: Evidence for Late-Time Internal Engine Activity

A. D. Falcone, D. N. Burrows, D. Lazzati +28

Until recently, X-ray flares during the afterglow of gamma ray bursts (GRBs) were a rarely detected phenomenon, thus their nature is unclear. During the afterglow of GRB 050502B, t…

astro-ph.GA2011

Planck early results. XV. Spectral energy distributions and radio continuum spectra of northern extragalactic radio sources

Planck Collaboration, J. Aatrokoski, P. A. R. Ade +246

Spectral energy distributions (SEDs) and radio continuum spectra are presented for a northern sample of 104 extragalactic radio sources, based on the Planck Early Release Compact S…

astro-ph2007

X-ray Flares in Early GRB Afterglows

D. N. Burrows, A. Falcone, G. Chincarini +12

The Swift X-ray Telescope (XRT) has discovered that flares are quite common in early X-ray afterglows of Gamma-Ray Bursts (GRBs), being observed in roughly 50% of afterglows with p…

astro-ph.HE2022

Long-term multi-wavelength study of 1ES 0647+250

MAGIC Collaboration, V. A. Acciari, T. Aniello +217

The BL Lac object 1ES 0647+250 is one of the few distant -ray emitting blazars detected at very high energies (VHE, 100 GeV) during a non-flaring state. It was detecte…

astro-ph.HE2009

Swift observations of the very intense flaring activity of Mrk 421 during 2006: I. Phenomenological picture of electron acceleration and predictions for the MeV/GeV emission

A. Tramacere, P. Giommi, M. Perri +2

We present results from a deep spectral analysis of all the Swift observations of Mrk 421 from April 2006 to July 2006, when it reached its largest X-ray flux recorded until 2006.…

astro-ph2006

The multiwavelength afterglow of GRB 050721: a puzzling rebrightening seen in the optical but not in the X-ray

L. A. Antonelli, V. Testa, P. Romano +27

Context. GRB050721 was detected by Swift and promptly followed-up, in the X-ray by Swift itself and, in the optical band, by the VLT operated, for the first time, in rapid response…

astro-ph.HE2021

X-ray spectra, light-curves and SEDs of blazars frequently observed by Swift

P. Giommi, M. Perri, M. Capalbi +19

Blazars research is one of the hot topics of contemporary extra-galactic astrophysics. That is because these sources are the most abundant type of extra-galactic gamma-ray sources…

astro-ph.IM2020

2SXPS: An improved and expanded Swift X-ray telescope point source catalog

P. A. Evans, K. L. Page, J. P. Osborne +8

We present the 2SXPS (Swift-XRT Point Source) catalog, containing 206,335 point sources detected by the Swift X-ray Telescope (XRT) in the 0.3--10 keV energy range. This catalog re…

astro-ph2001

The European Large Area ISO Survey V: a BeppoSAX hard X-ray survey of the S1 region

D. M. Alexander, F. La Franca, F. Fiore +18

We present BeppoSAX observations of the Southern S1 region in the European Large Area ISO Survey (ELAIS). These observations cover an area of ~1.7 sq. deg. and reach an on-axis (~0…

astro-ph.HE2016

First NuSTAR observations of the BL Lac - type blazar PKS~2155-304: constraints on the jet content and distribution of radiating particles

G. M. Madejski, K. Nalewajko, K. K. Madsen +35

We report the first hard X-ray observations with NuSTAR of the BL Lac type blazar PKS 2155-304, augmented with soft X-ray data from XMM-Newton and gamma-ray data from the Fermi Lar…

astro-ph2007

UVES/VLT high resolution spectroscopy of GRB 050730 afterglow: probing the features of the GRB environment

V. D'Elia, F. Fiore, E. Meurs +44

We analyze high resolution spectroscopic observations of the optical afterglow of GRB050730, obtained with UVES@VLT about hours after the GRB trigger. The spectrum shows that the I…

astro-ph.HE2014

Asymmetries in core-collapse supernovae from maps of radioactive Ti in CassiopeiaA

B. W. Grefenstette, F. A. Harrison, S. E. Boggs +28

Asymmetry is required by most numerical simulations of stellar core-collapse explosions, but the form it takes differs significantly among models. The spatial distribution of radio…

astro-ph2007

Swift multi-wavelength observations of the bright flaring burst GRB051117A

M. R. Goad, K. L. Page, O. Godet +13

We report on the temporal and spectral characteristics of the early X-ray emission from the Gamma Ray Burst 051117A as observed by Swift. The superb quality of the early X-ray ligh…

astro-ph.HE2021

The X-ray emission of the Seyfert 2 galaxy MCG-01-24-12

R. Middei, G. A. Matzeu, S. Bianchi +7

We present a detailed X-ray spectral analysis of the nearby Seyfert 2 galaxy MCG-01-24-12 based on a multi-epoch data set. Data have been taken with different X-ray satellites, nam…

astro-ph.HE2017

Cherenkov Telescope Array Contributions to the 35th International Cosmic Ray Conference (ICRC2017)

F. Acero, B. S. Acharya, V. Acín Portella +1137

List of contributions from the Cherenkov Telescope Array Consortium presented at the 35th International Cosmic Ray Conference, July 12-20 2017, Busan, Korea.

astro-ph.HE2015

Multiwavelength Study of Quiescent States of Mrk 421 with Unprecedented Hard X-Ray Coverage Provided by NuSTAR in 2013

M. Baloković, D. Paneque, G. Madejski +305

We present coordinated multiwavelength observations of the bright, nearby BL Lac object Mrk 421 taken in 2013 January-March, involving GASP-WEBT, Swift, NuSTAR, Fermi-LAT, MAGIC, V…

astro-ph.HE2019

Swift-XRT Follow-up of Gravitational Wave Triggers in the Second Advanced LIGO/Virgo Observing Run

N. J. Klingler, J. A. Kennea, P. A. Evans +37

The Neil Gehrels Swift Observatory carried out prompt searches for gravitational wave (GW) events detected by the LIGO/Virgo Collaboration (LVC) during the second observing run ("O…

astro-ph.HE2014

GRB 130427A: a Nearby Ordinary Monster

A. Maselli, A. Melandri, L. Nava +63

Long-duration Gamma-Ray Bursts (GRBs) are an extremely rare outcome of the collapse of massive stars, and are typically found in the distant Universe. Because of its intrinsic lumi…

astro-ph.HE2013

First Results from NuSTAR Observations of Mkn 421

M. Baloković, M. Ajello, R. D. Blandford +34

Mkn 421 is a nearby active galactic nucleus dominated at all wavelengths by a very broad non-thermal continuum thought to arise from a relativistic jet seen at a small angle to the…

astro-ph.HE2024

HERMES: Gamma Ray Burst and Gravitational Wave counterpart hunter

G. Ghirlanda, L. Nava, O. Salafia +67

Gamma Ray Bursts (GRBs) bridge relativistic astrophysics and multi-messenger astronomy. Space-based gamma/X-ray wide field detectors have proven essential to detect and localize th…

astro-ph.HE2013

The NuSTAR Extragalactic Survey: A First Sensitive Look at the High-Energy Cosmic X-ray Background Population

D. M. Alexander, D. Stern, A. Del Moro +31

We report on the first ten identifications of sources serendipitously detected by the NuSTAR to provide the first sensitive census of the cosmic X-ray background (CXB) source popul…

astro-ph.CO2012

Simultaneous Planck, Swift, and Fermi observations of X-ray and gamma-ray selected blazars

P. Giommi, G. Polenta, A. Lahteenmaki +92

We present simultaneous Planck, Swift, Fermi, and ground-based data for 105 blazars belonging to three samples with flux limits in the soft X-ray, hard X-ray, and gamma-ray bands.…

astro-ph2007

ROXA J081009.9+384757.0: a erg/s blazar with hard X-ray synchrotron peak or a new type of radio loud AGN?

P. Giommi, E. Massaro, P. Padovani +10

We report the discovery of ROXA J081009.9+384757.0 = SDSS J081009.9+384757.0, a z=3.95 blazar with a highly unusual Spectral Energy Distribution (SED). This object was first notice…

astro-ph2005

Swift-UVOT detection of GRB 050318

M. Still, P. W. A. Roming, K. O. Mason +27

We present observations of GRB 050318 by the Ultra-Violet and Optical Telescope (UVOT) on-board the Swift observatory. The data are the first detections of a Gamma Ray Burst (GRB)…

astro-ph2007

Testing the gamma-ray burst variability/peak luminosity correlation on a Swift homogeneous sample

D. Rizzuto, C. Guidorzi, P. Romano +10

We test the gamma-ray burst correlation between temporal variability and peak luminosity of the -ray profile on a homogeneous sample of 36 Swift/BAT GRBs with firm redshift det…

astro-ph2005

Prompt and afterglow early X-ray phases in the comoving frame. Evidence for Universal properties?

G. Chincarini, A. Moretti, P. Romano +38

We analyze the Swift XRT light curves and spectra of the gamma-ray bursts (GRBs) for which the redshift has been measured. The sample consists of seven GRBs. The soft X-ray light c…

astro-ph2005

Swift XRT Observations of the Afterglow of GRB 050319

G. Cusumano, V. Mangano, L. Angelini +27

Swift discovered the high redshift GRB 050319 with the Burst Alert Telescope and began observing with its narrow field instruments only 225 s after the burst onset. The afterglow X…

astro-ph1998

X-Ray Surveys

P. Giommi, F. Fiore, M. Perri

A review of recent developments in the field of X-ray surveys, especially in the hard (2-10 and 5-10 keV) bands, is given. A new detailed comparison between the measurements in the…

astro-ph2004

Log-parabolic spectra and particle acceleration in blazars - II: The BeppoSAX wide band X-ray spectra of Mkn 501

E. Massaro, M. Perri, P. Giommi +2

We present the results of a spectral and temporal study of the complete set of BeppoSAX NFI (11) and WFC (71) observations of the BL Lac object Mkn 501. The WFC 2-28 keV data, repo…

astro-ph.HE2020

Swift-XRT follow-up of gravitational wave triggers during the third aLIGO/Virgo observing run

K. L. Page, P. A. Evans, A. Tohuvavohu +41

The Neil Gehrels Swift Observatory followed up 18 gravitational wave (GW) triggers from the LIGO/Virgo collaboration during the O3 observing run in 2019/2020, performing approximat…

astro-ph.HE2016

Supplement: Localization and broadband follow-up of the gravitational-wave transient GW150914

B. P. Abbott, R. Abbott, T. D. Abbott +1538

This Supplement provides supporting material for arXiv:1602.08492 . We briefly summarize past electromagnetic (EM) follow-up efforts as well as the organization and policy of the c…

astro-ph2006

The early X-ray emission from GRBs

P. T. O'Brien, R. Willingale, J. Osborne +29

We present observations of the early X-ray emission for a sample of 40 gamma-ray bursts (GRBs) obtained using the Swift satellite for which the narrow-field instruments were pointe…

astro-ph.IM2013

The seven year Swift-XRT point source catalog (1SWXRT)

V. D'Elia, M. Perri, S. Puccetti +14

Swift is a multi-wavelength observatory specifically designed for gamma-ray burst (GRB) astronomy that is operational since 2004. Swift is also a very flexible multi-purpose facili…

astro-ph2007

Attributes of flares in Gamma Ray Bursts: sample I

G. Chincarini, A. Moretti, P. Romano +14

We discuss some of the preliminary results and findings derived from the analysis of a first sample of flares detected by the XRT on board Swift. The analysis shows that the morpho…

astro-ph.HE2024

IXPE observation confirms a high spin in the accreting black hole 4U 1957+115

L. Marra, M. Brigitte, N. Rodriguez Cavero +113

We present the results of the first X-ray polarimetric observation of the low-mass X-ray binary 4U 1957+115, performed with the Imaging X-ray Polarimetry Explorer in May 2023. The…

astro-ph.CO2009

A glimpse of the end of the dark ages: the gamma-ray burst of 23 April 2009 at redshift 8.3

N. R. Tanvir, D. B. Fox, A. J. Levan +59

It is thought that the first generations of massive stars in the Universe were an important, and quite possibly dominant, source of the ultra-violet radiation that reionized the hy…

astro-ph2008

The Swift X-Ray Telescope: Status and Performance

David N. Burrows, J. A. Kennea, A. F. Abbey +23

We present science highlights and performance from the Swift X-ray Telescope (XRT), which was launched on November 20, 2004. The XRT covers the 0.2-10 keV band, and spends most of…

astro-ph2003

What Types of Jets does Nature Make: A New Population of Radio Quasars

P. Padovani, E. Perlman, H. Landt +2

We use statistical results from a large sample of about 500 blazars, based on two surveys, the Deep X-ray Radio Blazar Survey (DXRBS), nearly complete, and the RASS-Green Bank surv…

astro-ph2007

A study of the prompt and afterglow emission of the Short GRB 061201

G. Stratta, P. D'Avanzo, S. Piranomonte +30

Our knowledge of the intrinsic properties of short duration Gamma-Ray Bursts has relied, so far, only upon a few cases for which the estimate of the distance and an extended, multi…

astro-ph.HE2022

Polarization constraints on the X-ray corona in Seyfert Galaxies: MCG-05-23-16

A. Marinucci, F. Muleri, M. Dovčiak +97

We report on the first observation of a radio-quiet Active Galactic Nucleus (AGN) using polarized X-rays: the Seyfert 1.9 galaxy MCG-05-23-16. This source was pointed with the Imag…

astro-ph.GA2023

Uncovering the geometry of the hot X-ray corona in the Seyfert galaxy NGC4151 with IXPE

V. E. Gianolli, D. E. Kim, S. Bianchi +106

We present an X-ray spectro-polarimetric analysis of the bright Seyfert galaxy NGC4151. The source has been observed with the Imaging X-ray Polarimetry Explorer (IXPE) for 700 ks,…

astro-ph.HE2018

The extreme HBL behaviour of Markarian 501 during 2012

M. L. Ahnen, S. Ansoldi, L. A. Antonelli +276

A multiwavelength campaign was organized to take place between March and July of 2012. Excellent temporal coverage was obtained with more than 25 instruments, including the MAGIC,…

astro-ph2005

Log-parabolic spectra and particle acceleration in blazars. III: SSC emission in the TeV band from Mkn 501

E. Massaro, A. Tramacere, M. Perri +2

Curved broad-band spectral distributions of non-thermal sources like blazars are described well by a log-parabolic (LP) law where the second degree term measures the curvature. LP…

astro-ph.HE2009

Evidence for an anticorrelation between the duration of the shallow decay phase of GRB X-ray afterglows and redshift

G. Stratta, D. Guetta, V. D'Elia +3

One of the most intriguing features discovered by Swift is a plateau phase in the X-ray flux decay of about 70% of the afterglows of gamma-ray bursts (GRBs). The physical origin of…

astro-ph2007

Swift observations of GRB 060614: an anomalous burst with a well behaved afterglow

V. Mangano, S. T. Holland, D. Malesani +22

GRB 060614 is a remarkable GRB observed by Swift with puzzling properties, which challenge current progenitor models. The lack of any bright SN down to very strict limits and the v…

astro-ph.IM2019

Monte Carlo studies for the optimisation of the Cherenkov Telescope Array layout

A. Acharyya, I. Agudo, E. O. Angüner +467

The Cherenkov Telescope Array (CTA) is the major next-generation observatory for ground-based very-high-energy gamma-ray astronomy. It will improve the sensitivity of current groun…

astro-ph2007

GRB 060714: No Clear Dividing Line Between Prompt Emission and X-ray Flares

H. A. Krimm, J. Granot, F. Marshal +6

The long gamma-ray burst GRB 060714 was observed to exhibit a series of five X-ray flares beginning ~70 s after the burst trigger T0 and continuing until T0 + ~200 s. The first two…

astro-ph.HE2020

The Open Universe survey of Swift-XRT GRB fields: a complete sample of HBL blazars

P. Giommi, Y. L. Chang, S. Turriziani +22

We have analysed all the X-ray images centred on Gamma Ray Bursts generated by Swift over the last 15 years using automatic tools that do not require any expertise in X-ray astrono…

astro-ph2008

Modelling the spectral response of the Swift-XRT CCD camera: Experience learnt from in-flight calibration

O. Godet, A. P. Beardmore, A. F. Abbey +11

(Abbreviated) We show that the XRT spectral response calibration was complicated by various energy offsets in photon counting (PC) and windowed timing (WT) modes related to the way…

astro-ph2007

The 26 year-long X-ray light curve and the X-ray spectrum of the BL Lac Object 1E 1207.9+3945 in its brightest state

A. Maselli, P. Giommi, M. Perri +4

We studied the temporal and spectral evolution of the synchrotron emission from the high energy peaked BL Lac object 1E 1207.9+3945. Two recent observations have been performed by…

astro-ph.HE2016

The NuSTAR Extragalactic Surveys: The Number Counts of Active Galactic Nuclei and the Resolved Fraction of the Cosmic X-ray Background

F. A. Harrison, J. Aird, F. Civano +41

We present the 3-8 keV and 8-24 keV number counts of active galactic nuclei (AGN) identified in the NuSTAR extragalactic surveys. NuSTAR has now resolved 33-39% of the X-ray backgr…

astro-ph2000

The Cosmological Evolution of BL Lacertae Objects

P. Giommi, A. Pellizzoni, M. Perri +1

We review the main results from several radio, X-ray and multi-frequency surveys on the topic of cosmological evolution of BL Lacertae objects. Updated findings on BL Lac evolution…

astro-ph.HE2025

Insights from the first flaring activity of a high-synchrotron-peaked blazar with X-ray polarization and VHE gamma rays

MAGIC Collaboration, K. Abe, S. Abe +250

We study a flaring activity of the HSP Mrk421 that was characterized from radio to very-high-energy (VHE; E TeV) gamma rays with MAGIC, Fermi-LAT, Swift, XMM-Newton and sever…

astro-ph2000

The BeppoSAX 2-10 keV Survey

P. Giommi, M. Perri, F. Fiore

We present the results of a 2-10 keV BeppoSAX survey based on 140 high galactic latitude MECS fields, 12 of which are deep exposures of ``blank'' parts of the sky. The limiting sen…

astro-ph.HE2024

The Northern Cross Fast Radio Burst project IV. Multi-wavelength study of the actively repeating FRB 20220912A

D. Pelliciari, G. Bernardi, M. Pilia +26

Fast radio bursts (FRBs) are energetic, millisecond-duration radio pulses observed at extragalactic distances and whose origins are still a subject of heated debate. A fraction of…

astro-ph2007

GRB 050410 and GRB 050412: are they really dark GRBs?

T. Mineo, V. Mangano, S. Covino +20

We present a detailed analysis of the prompt and afterglow emission of GRB 050410 and GRB 050412 detected by Swift for which no optical counterpart was observed. The 15-150 keV ene…

astro-ph2006

X-ray flare in XRF 050406: evidence for prolonged engine activity

P. Romano, A. Moretti, P. L. Banat +33

We present observations of XRF 050406, the first burst detected by Swift showing a flare in its X-ray light curve. During this flare, which peaks at t_peak ~210s after the BAT trig…

astro-ph.HE2023

Swift/UVOT discovery of Swift J221951-484240: a UV luminous ambiguous nuclear transient

S. R. Oates, N. P. M. Kuin, M. Nicholl +57

We report the discovery of Swift J221951-484240 (hereafter: J221951), a luminous slow-evolving blue transient that was detected by the Neil Gehrels Swift Observatory Ultra-violet/O…

astro-ph.HE2013

1SXPS: A deep Swift X-ray Telescope point source catalog with light curves and spectra

P. A. Evans, J. P. Osborne, A. P. Beardmore +9

We present the 1SXPS (Swift-XRT Point Source) catalog of 151,524 X-ray point-sources detected by the Swift-XRT in 8 years of operation. The catalog covers 1905 square degrees distr…

astro-ph.HE2022

Accretion geometry of the neutron star low mass X-ray binary Cyg X-2 from X-ray polarization measurements

R. Farinelli, S. Fabiani, J. Poutanen +92

We report spectro-polarimetric results of an observational campaign of the bright neutron star low-mass X-ray binary Cyg X-2 simultaneously observed by IXPE, NICER and INTEGRAL. Co…

astro-ph2007

The short GRB 051210 observed by Swift

V. La Parola, V. Mangano, B. Zhang +12

We report on the short GRB051210 detected by the Swift-BAT. The light curve, on which we focus mainly, shows a hint of extended emission in the BAT energy range, a steep decay of t…

astro-ph.HE2025

IXPE Observations of the Blazar Mrk 501 in 2022: A Multiwavelength View

L. Lisalda, E. Gau, H. Krawczynski +157

The blazar Markarian 501 (Mrk 501) was observed on three occasions over a 4-month period between 2022 March and 2022 July with the Imaging X-ray Polarimetry Explorer (IXPE). In thi…

astro-ph.HE2025

Characterization of Markarian 421 during its most violent year: Multiwavelength variability and correlations

K. Abe, S. Abe, J. Abhir +212

Mrk 421 was in its most active state around early 2010, which led to the highest TeV gamma-ray flux ever recorded from any active galactic nuclei. We aim to characterize the multiw…

astro-ph.HE2021

Swift/UVOT follow-up of Gravitational Wave Alerts in the O3 era

S. R. Oates, F. E. Marshall, A. A. Breeveld +41

In this paper, we report on the observational performance of the Swift Ultra-violet/Optical Telescope (UVOT) in response to the Gravitational Wave alerts announced by the Advanced…

astro-ph.IM2024

Design and development of the HERMES Pathfinder payloads

R. Campana, Y. Evangelista, F. Fiore +22

HERMES (High Energy Rapid Modular Ensemble of Satellites) Pathfinder mission aims to observe and localize Gamma Ray Bursts (GRBs) and other transients using a constellation of nano…

astro-ph.HE2023

X-ray polarimetry of X-ray pulsar X Persei: another orthogonal rotator?

A. A. Mushtukov, S. S. Tsygankov, J. Poutanen +103

X Persei is a persistent low-luminosity X-ray pulsar of period of 835 s in a Be binary system. The field strength at the neutron star surface is not known precisely, but indi…

astro-ph.HE2020

Multiwavelength variability and correlation studies of Mrk 421 during historically low X-ray and -ray activity in 20152016

MAGIC Collaboration, V. A. Acciari, S. Ansoldi +224

We report a characterization of the multi-band flux variability and correlations of the nearby (z=0.031) blazar Markarian 421 (Mrk 421) using data from Metsähovi, Swift, Fermi-LAT…

astro-ph.IM2017

ASTRI SST-2M prototype and mini-array simulation chain, data reduction software, and archive in the framework of the Cherenkov Telescope Array

S. Lombardi, C. Bigongiari, S. Gallozzi +10

The Cherenkov Telescope Array (CTA) is a worldwide project aimed at building the next-generation ground-based gamma-ray observatory. Within the CTA project, the Italian National In…

astro-ph.IM2012

Timing accuracy of the Swift X-Ray Telescope in WT mode

G. Cusumano, V. La Parola, M. Capalbi +8

The X-Ray Telescope (XRT) on board Swift was mainly designed to provide detailed position, timing and spectroscopic information on Gamma-Ray Burst (GRB) afterglows. During the miss…

astro-ph2005

Bright X-ray Flares in Gamma-Ray Burst Afterglows

D. N. Burrows, P. Romano, A. Falcone +31

Gamma-ray burst (GRB) afterglows have provided important clues to the nature of these massive explosive events, providing direct information on the nearby environment and indirect…

astro-ph.HE2015

NuSTAR and multifrequency study of the two high-redshift blazars S5 0836+710 and PKS 2149-306

G. Tagliaferri, G. Ghisellini, M. Perri +15

The most powerful blazars are the flat spectrum radio quasars whose emission is dominated by a Compton component peaking between a few hundred keV and a few hundred MeV. We selecte…

astro-ph2006

GRB 050505: A high redshift burst discovered by Swift

C. P. Hurkett, J. P. Osborne, K. L. Page +18

We report the discovery and subsequent multi-wavelength afterglow behaviour of the high redshift (z = 4.27) Gamma Ray Burst GRB 050505. This burst is the third most distant burst,…

astro-ph.HE2023

The X-ray polarisation of the Seyfert 1 galaxy IC 4329A

A. Ingram, M. Ewing, A. Marinucci +105

We present an X-ray spectro-polarimetric analysis of the bright Seyfert galaxy IC 4329A. The Imaging X-ray Polarimetry Explorer (IXPE) observed the source for ~500 ks, supported by…