350 results on '"Bodaghee, A."'
Search Results
302. The nature of the X-ray binary IGR J19294+1816from INTEGRAL, RXTE, and Swiftobservations
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Rodriguez, J., Tomsick, J. A., Bodaghee, A., Zurita Heras, J.-A., Chaty, S., Paizis, A., Corbel, S., Rodriguez, J., Tomsick, J. A., Bodaghee, A., Zurita Heras, J.-A., Chaty, S., Paizis, A., and Corbel, S. more...
- Abstract
We report the results of a high-energy multi-instrumental campaign with INTEGRAL, RXTE, and Swiftof the recently discovered INTEGRALsource IGR J19294+1816. The Swift/XRT data allow us to refine the position of the source to ${\mathrm{RA}}_{\mathrm{J}2000}$= $19^{\mathrm h} 29^{\mathrm m} 55.9^{\mathrm s}$${\mathrm{Dec}}_{\mathrm{J}2000}$= +18° 18′38.4″ (±3.5″), which in turn permits us to identify a candidate infrared counterpart. The Swiftand RXTEspectra are well fitted with absorbed power laws with hard (Γ~ 1) photon indices. During the longest Swiftobservation, we obtained evidence of absorption in true excess to the Galactic value, which may indicate some intrinsic absorption in this source. We detected a strong ($P = 40$%) pulsation at 12.43781 (±0.00003) s that we interpret as the spin period of a pulsar. All these results, coupled with the possible 117 day orbital period, point to IGR J19294+1816being an HMXB with a Be companion star. However, while the long-term INTEGRAL/IBIS/ISGRI 18-40 keV light curve shows that the source spends most of its time in an undetectable state, we detect occurrences of short (~$2000{-}3000$s) and intense flares that are more typical of supergiant fast X-ray transients. We therefore cannot make firm conclusions on the type of system, and we discuss the possible implications of IGR J19294+1816being an SFXT. more...
- Published
- 2009
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303. A description of sources detected by INTEGRALduring the first 4 years of observations
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Bodaghee, A., Courvoisier, T. J.-L., Rodriguez, J., Beckmann, V., Produit, N., Hannikainen, D., Kuulkers, E., Willis, D. R., Wendt, G., Bodaghee, A., Courvoisier, T. J.-L., Rodriguez, J., Beckmann, V., Produit, N., Hannikainen, D., Kuulkers, E., Willis, D. R., and Wendt, G. more...
- Abstract
Context.In its first 4 years of observing the sky above 20 keV, INTEGRAL-ISGRI has detected 500 sources, around half of which are new or unknown at these energies. Follow-up observations at other wavelengths revealed that some of these sources feature unusually large column densities, long pulsations, and other interesting characteristics. more...
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- 2007
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304. IGR J17252-3616: an accreting pulsar observed by INTEGRALand XMM-Newton
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Zurita Heras, J. A., De Cesare, G., Walter, R., Bodaghee, A., Bélanger, G., Courvoisier, T. J.-L., Shaw, S. E., Stephen, J. B., Zurita Heras, J. A., De Cesare, G., Walter, R., Bodaghee, A., Bélanger, G., Courvoisier, T. J.-L., Shaw, S. E., and Stephen, J. B. more...
- Abstract
The discovery of the X-ray source IGR J17252-3616by INTEGRALwas reported on 9 February 2004. Regular monitoring by INTEGRALshows that IGR J17252-3616is a persistent hard X-ray source with an average count rate of 0.96 counts$\,\mathrm{s}^{-1}$(~6.4 mCrab) in the 20–60 keV energy band. A follow-up observation with XMM-Newtonwhich was performed on March 21, 2004, showed that the source is located at RA (2000.0) = $17^{\rm h}25^{\rm m}11.4^{\rm s}$and Dec = $-36\degr 16\arcmin 58.6\arcsec$with an uncertainty of $4\arcsec$. The only infra-red counterpart to be found within the XMM-Newtonerror circle was 2MASS J17251139-3616575, which has a Ks-band magnitude of 10.7 and is located 1″ away from the XMM-Newtonposition. The analysis of the combined INTEGRALand XMM-Newtonobservations shows that the source is a binary X-ray pulsar with a spin period of 413.7 s and an orbital period of 9.72 days. The spectrum can be fitted with a flat power law plus an energy cut off ($\Gamma \sim 0.02,E_{\mathrm{c}} \sim 8.2\,\mathrm{keV}$) or a Comptonized model ($kT_{\textrm{\tiny e}}\sim 5.5\,\mathrm{keV}, \tau\sim 7.8$). The spectrum also indicates a large hydrogen column density of $N_{\mathrm{H}}\sim 15\times 10^{22}\,\mathrm{atoms}\,\mathrm{cm}^{-2}$suggesting an intrinsic absorption. The Fe Kαline at 6.4 keV is clearly detected. Phase-resolved spectroscopy does not show any variation in the continuum except the total emitted flux. The absorption is constant along the pulse phase. This source can be associated with EXO 1722-363as both systems show common timing and spectral features. The observations suggest that the source is a wind-fed accreting pulsar accompanied by a supergiant star. more...
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- 2006
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305. High-energy sources before INTEGRAL*
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Ebisawa, K., Bourban, G., Bodaghee, A., Mowlavi, N., Courvoisier, T. J.-L., Ebisawa, K., Bourban, G., Bodaghee, A., Mowlavi, N., and Courvoisier, T. J.-L.
- Abstract
We describe the INTEGRAL reference catalog which classifies previously known bright X-ray and gamma-ray sources before the launch of INTEGRAL. These sources are, or have been at least once, brighter than ~1 mCrab above 3 keV, and are expected to be detected by INTEGRAL. This catalog is being used in the INTEGRAL Quick Look Analysisto discover new sources or significantly variable sources. We compiled several published X-ray and gamma-ray catalogs, and surveyed recent publications for new sources. Consequently, there are 1122 sources in our INTEGRAL reference catalog. In addition to the source positions, we show an approximate spectral model and expected flux for each source, based on which we derive expected INTEGRAL counting rates. Assuming the default instrument performances and at least ~ 105s exposure time for any part of the sky, we expect that INTEGRAL will detect at least ~700 sources below 10 keV and ~400 sources above 20 keV over the mission life. more...
- Published
- 2003
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306. Near-infrared spectroscopy of 20 new Chandra sources in the Norma arm.
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Rahoui, F., Tomsick, J. A., Fornasini, F. M., Bodaghee, A., and Bauer, F. E.
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X-ray binaries ,NEAR infrared spectroscopy ,CATACLYSMIC variable stars ,DWARF stars ,STELLAR mass ,STELLAR photometry - Abstract
We report on CTIO/NEWFIRM and CTIO/OSIRIS photometric and spectroscopic observations of 20 new X-ray (0.5–10 keV) emitters discovered in the Norma arm Region Chandra Survey (NARCS). NEWFIRM photometry was obtained to pinpoint the nearinfrared counterparts of NARCS sources, while OSIRIS spectroscopy was used to help identify 20 sources with possible high mass X-ray binary properties. We find that (1) two sources are WN8 Wolf-Rayet stars, maybe in colliding wind binaries, part of the massive star cluster Mercer 81; (2) two are emission-line stars, possibly in X-ray binaries, that exhibit near- and mid-infrared excesses either due to free-free emission from the decretion discs of Be stars or warm dust in the stellar winds of peculiar massive stars such as B[e] supergiants or luminous blue variables; (3) one is a B8-A3 IV-V star that could be in a quiescent high mass X-ray binary system; (4) two are cataclysmic variables including one intermediate polar; (5) three may be neutron star symbiotic binaries; (6) five are most likely white dwarf symbiotic binaries; and (7) five exhibit properties more consistent with isolated giant/dwarf stars. The possible detection of one to three high mass X-ray binaries is in good agreement with our predictions. However, our study illustrates the difficulty of clearly differentiating quiescent or intermediate X-ray luminosity systems from isolated massive stars, which may lead to an underestimation of the number of known high mass X-ray binaries. [ABSTRACT FROM AUTHOR] more...
- Published
- 2014
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307. XMM-NEWTON FINDS THAT SAX J1750.8-2900 MAY HARBOR THE HOTTEST, MOST LUMINOUS KNOWN NEUTRON STAR.
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LOWELL, A. W., TOMSICK, J. A., HEINKE, C. O., BODAGHEE, A., BOGGS, S. E., KAARET, P., CHATY, S., RODRIGUEZ, J., and WALTER, R.
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NEUTRON stars ,X-ray spectra ,POWER law (Mathematics) ,LUMINOSITY ,TEMPERATURE of stars ,THERMODYNAMIC equilibrium - Abstract
We have performed the first sensitive X-ray observation of the low-mass X-ray binary (LMXB) SAX J1750.8 -2900 in quiescence with XMM-Newton. The spectrum was fit to both a classical blackbody model, and a non-magnetized, pure hydrogen neutron star (NS) atmosphere model. A power-law component was added to these models, but we found that it was not required by the fits. The distance to SAX J1750.8-2900 is known to be D = 6.79 kpc from a previous analysis of photospheric radius expansion bursts. This distance implies a bolometric luminosity (as given by the NS atmosphere model) of (1.05 ±0.12) x 10
34 (D/6.79 kpc)² erg s-1 , which is the highest known luminosity for a NS LMXB in quiescence. One simple explanation for this surprising result could be that the crust and core of the NS were not in thermal equilibrium during the observation. We argue that this was likely not the case, and that the core temperature of the NS in SAX J1750.8-2900 is unusually high. [ABSTRACT FROM AUTHOR] more...- Published
- 2012
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308. CLUSTERING BETWEEN HIGH-MASS X-RAY BINARIES AND OB ASSOCIATIONS IN THE MILKY WAY.
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Bodaghee, A., Tomsick, J. A., Rodriguez, J., and James, J. B.
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X-ray binaries , *MILKY Way , *GALAXIES , *SUPERGIANT stars , *BINARY stars , *X-ray astronomy - Abstract
We present the first direct measurement of the spatial cross-correlation function of high-mass X-ray binaries (HMXBs) and active OB star-forming complexes in the Milky Way. This result relied on a sample containing 79 hard X-ray-selected HMXBs and 458 OB associations. Clustering between the two populations is detected with significance above 7σ for distances < 1 kpc. Thus, HMXBs closely trace the underlying distribution of the massive star-forming regions that are expected to produce the progenitor stars of HMXBs. The average offset of 0.4 ± 0.2 kpc between HMXBs and OB associations is consistent with being due to natal kicks at velocities of the order of 100 ± 50 km s-1. The characteristic scale of the correlation function suggests an average kinematical age (since the supernova phase) of ~4 Myr for the HMXB population. Despite being derived from a global view of our Galaxy, these signatures of HMXB evolution are consistent with theoretical expectations as well as observations of individual objects. [ABSTRACT FROM AUTHOR] more...
- Published
- 2012
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309. BROADBAND SUZAKU OBSERVATIONS OF IGR J16207-5129.
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Bodaghee, A., Tomsick, J. A., Rodriguez, J., Chaty, S., Pottschmidt, K., and Walter, R.
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- 2010
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310. INTEGRAL and XMM–Newton observations of the X-ray pulsar IGR J16320−4751/AX J1631.9−4752.
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Rodriguez, J., Bodaghee, A., Kaaret, P., Tomsick, J. A., Kuulkers, E., Malaguti, G., Petrucci, P.-O., Cabanac, C., Chernyakova, M., Corbel, S., Deluit, S., Di Cocco, G., Ebisawa, K., Goldwurm, A., Henri, G., Lebrun, F., Paizis, A., Walter, R., and Foschini, L. more...
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ASTRONOMY , *PULSARS , *X-ray binaries , *X-ray astronomy , *SPECTRUM analysis , *X-ray spectroscopy - Abstract
We report on observations of the X-ray pulsar IGR J16320−4751 (also known as AX J1631.9−4752) performed simultaneously with International Gamma-Ray Astrophysics Laboratory ( INTEGRAL) and XMM–Newton. We refine the source position and identify the most likely infrared counterpart. Our simultaneous coverage allows us to confirm the presence of X-ray pulsations at ∼1300 s, that we detect above 20 keV with INTEGRAL for the first time. The pulse fraction is consistent with being constant with energy, which is compatible with a model of polar accretion by a pulsar. We study the spectral properties of IGR J16320−4751 during two major periods occurring during the simultaneous coverage with both satellites, namely a flare and a non-flare period. We detect the presence of a narrow 6.4 keV iron line in both periods. The presence of such a feature is typical of supergiant wind accretors such as Vela X-1 or GX 301−2. We inspect the spectral variations with respect to the pulse phase during the non-flare period, and show that the pulse is solely due to variations of the X-ray flux emitted by the source and not due to variations of the spectral parameters. Our results are therefore compatible with the source being a pulsar in a High Mass X-ray Binary. We detect a soft excess appearing in the spectra as a blackbody with a temperature of ∼0.07 keV. We discuss the origin of the X-ray emission in IGR J16320−4751: while the hard X-rays are likely the result of Compton emission produced in the close vicinity of the pulsar, based on energy argument we suggest that the soft excess is likely the emission by a collisionally energized cloud in which the compact object is embedded. [ABSTRACT FROM AUTHOR] more...
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- 2006
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311. NuSTAR Hard X-ray Survey of the Galactic Center Region II: X-ray Point Sources
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Hong, Jaesub, Mori, Kaya, Hailey, Charles J., Nynka, Melania, Zhang, Shuo, Gotthelf, Eric, Fornasini, Francesca M., Krivonos, Roman, Bauer, Franz, Perez, Kerstin, Tomsick, John A., Bodaghee, Arash, Chiu, Jeng-Lun, Clavel, Maïca, Stern, Daniel, Grindlay, Jonathan E., Alexander, David M., Aramaki, Tsuguo, Baganoff, Frederick K., Barret, Didier, Barrière, Nicolas, Boggs, Steven E., Canipe, Alicia M., Christensen, Finn E., Craig, William W., Desai, Meera A., Forster, Karl, Giommi, Paolo, Grefenstette, Brian W., Harrison, Fiona A., Hong, Dooran, Hornstrup, Allan, Kitaguchi, Takao, Koglin, Jason E., Madsen, Kristen K., Mao, Peter H., Miyasaka, Hiromasa, Perri, Matteo, Pivovaroff, Michael J., Puccetti, Simonetta, Rana, Vikram, Westergaard, Niels J., Zhang, William W., and Zoglauer, Andreas more...
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Galaxy: center ,X-rays: binaries ,X-rays: diffuse background ,X-rays: general - Abstract
We present the first survey results of hard X-ray point sources in the Galactic Center (GC) region by NuSTAR. We have discovered 70 hard (3–79 keV) X-ray point sources in a 0.6 deg${}^{2}$ region around Sgr A* with a total exposure of 1.7 Ms, and 7 sources in the Sgr B2 field with 300 ks. We identify clear Chandra counterparts for 58 NuSTAR sources and assign candidate counterparts for the remaining 19. The NuSTAR survey reaches X-ray luminosities of ~4× and ~8 × 10${}^{32}$ erg s${}^{-1}$ at the GC (8 kpc) in the 3–10 and 10–40 keV bands, respectively. The source list includes three persistent luminous X-ray binaries (XBs) and the likely run-away pulsar called the Cannonball. New source-detection significance maps reveal a cluster of hard (>10 keV) X-ray sources near the Sgr A diffuse complex with no clear soft X-ray counterparts. The severe extinction observed in the Chandra spectra indicates that all the NuSTAR sources are in the central bulge or are of extragalactic origin. Spectral analysis of relatively bright NuSTAR sources suggests that magnetic cataclysmic variables constitute a large fraction (>40%–60%). Both spectral analysis and logN–logS distributions of the NuSTAR sources indicate that the X-ray spectra of the NuSTAR sources should have kT > 20 keV on average for a single temperature thermal plasma model or an average photon index of Γ = 1.5–2 for a power-law model. These findings suggest that the GC X-ray source population may contain a larger fraction of XBs with high plasma temperatures than the field population., Astronomy more...
- Published
- 2016
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312. GX 339-4 detected with INTEGRAL
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Kuulkers, E., Bodaghee, A., Foschini, L., Guainazzi, M., Matt, G., Israel, G., Fabrizio Nicastro, Oosterbroek, T., Parmar, A., Rodriguez, J., Walter, R., Kuulkers, E., Bodaghee, A., Foschini, L., Guainazzi, M., Matt, Giorgio, Israel, G., Nicastro, F., Oosterbroek, T., Parmar, A., Rodriguez, J., and Walter, R. more...
- Abstract
GX 339-4 was in the field of view during an observation of IGR J16318-4848 with INTEGRAL (UT 2004 Feb 18 03:41 - Feb 18 17:29). Further to the increase in activity reported in the optical/radio (ATel #230) and X-rays (ATel #231, #236), we report the detection of GX 339-4 with Jem-X and ISGRI/IBIS onboard INTEGRAL. Between 2004 Feb 18 03:41 - 10:09 (UT) the average observed fluxes were ~37 mCrab, ~46 mCrab, ~24 mCrab, and ~38 mCrab, in, respectively the 3-10 keV, 10-31 keV (Jem-X), 20-60 keV, and 60-200 keV (ISGRI/IBIS) energy bands. more...
313. Neutron Stars and Black Holes in the Small Magellanic Cloud: The SMC NuSTAR Legacy Survey.
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M. Lazzarini, B. F. Williams, A. E. Hornschemeier, V. Antoniou, G. Vasilopoulos, F. Haberl, N. Vulic, M. Yukita, A. Zezas, A. Bodaghee, B. D. Lehmer, T. J. Maccarone, A. Ptak, D. Wik, F. M. Fornasini, Jaesub Hong, J. A. Kennea, J. A. Tomsick, T. Venters, and A. Udalski more...
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SMALL magellanic cloud ,NEUTRON stars ,HARD X-rays ,MAGELLANIC clouds ,BLACK holes ,X-ray binaries ,PULSARS - Abstract
We present a source catalog from the first deep hard X-ray (E > 10 keV) survey of the Small Magellanic Cloud (SMC), the Nuclear Spectroscopic Telescope Array (NuSTAR) Legacy Survey of the SMC. We observed three fields, for a total exposure time of 1 Ms, along the bar of this nearby star-forming galaxy. Fields were chosen for their young stellar and accreting binary populations. We detected 10 sources above a 3σ significance level (4–25 keV) and obtained upper limits on an additional 40 sources. We reached a 3σ limiting luminosity in the 4–25 keV band of ∼10
35 erg s−1 , allowing us to probe fainter X-ray binary (XRB) populations than has been possible with other extragalactic NuSTAR surveys. We used hard X-ray colors and luminosities to constrain the compact-object type, exploiting the spectral differences between accreting black holes and neutron stars at E > 10 keV. Several of our sources demonstrate variability consistent with previously observed behavior. We confirmed pulsations for seven pulsars in our 3σ sample. We present the first detection of pulsations from a Be-XRB, SXP 305 (CXO J005215.4–73191), with an X-ray pulse period of 305.69 ± 0.16 s and a likely orbital period of ∼1160–1180 days. Bright sources (≳5 × 1036 erg s−1 ) in our sample have compact-object classifications consistent with their previously reported types in the literature. Lower-luminosity sources (≲5 × 1036 erg s−1 ) have X-ray colors and luminosities consistent with multiple classifications. We raise questions about possible spectral differences at low luminosity between SMC pulsars and the Galactic pulsars used to create the diagnostic diagrams. [ABSTRACT FROM AUTHOR] more...- Published
- 2019
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314. IGR J17252-3616: An Eclipsing Pulsar Observed by INTEGRAL and XMM-Newton
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Zurita Heras, J. A., Giovanni De Cesare, Walter, R., Bodaghee, A., Bélanger, G., Courvoisier, T. J. -L, Shaw, S. E., and Stephen, J. B.
315. NuSTAR Observations of SMC X-3
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Pottschmidt, K., Ballhausen, R., Joern Wilms, Zezas, A., Fuerst, F., Nowak, M. A., Grinberg, V., Kuehnel, M., Kretschmar, P., Tomsick, J. A., Antoniou, V., Kennea, J., Hong, J., Haberl, F., Maccarone, T., Hornschemeier, A., Ptak, A., Yukita, M., Wik, D., Lehmer, B., Fornasini, F., Bodaghee, A., and Mcbride, V. more...
316. Chemical abundances of planet-host stars Results for alpha and Fe-group elements
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Michel Mayor, Garik Israelian, Arash Bodaghee, and Nuno C. Santos
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Physics ,Field (physics) ,Astrophysics (astro-ph) ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Chemical evolution ,Stars ,Space and Planetary Science ,Planet ,Abundance (ecology) ,Group (periodic table) ,Astrophysics::Solar and Stellar Astrophysics ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics::Galaxy Astrophysics - Abstract
In this paper, we present a study of the abundances of Si, Ca, Sc, Ti, V, Cr, Mn, Co, and Ni in a large set of stars known to harbor giant planets, as well as in a comparison sample of stars not known to have any planet ary-mass companions. We have checked for possible chemical differences between planet hosts and field stars without known planets. Our results show that overall, and for a given value of [Fe/H], the abundance trends for the planet hosts are nearly indistinguishable from those of the field stars. In general, the trends show no discontinuities,and the abundance distributions of stars with giant planets are high [Fe/H] extensions to the curves traced by the field dwarfs without planets. The only elements that might present slight differences between the two groups of stars are V, Mn, and to a lesser extent Ti and Co. We also use the available data to describe galactic chemical evolution trends for the elements studied. When comparing the results with former studies, a few differences emerge for the high [Fe/H] tail of the distribution, a region that is sampled with unprecedented detail in our analysis., Accepted for publication in Astronomy & Astrophysics more...
317. INTEGRAL observations of SAX J1808.4-3658 currently in outburst
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Del Santo, M., Bozzo, E., Kuulkers, E., Bazzano, A., Beckmann, V., Bird, T., Bodaghee, A., Chenevez, J., Domingo, A., Jonker, P., Kretschmar, P., Markwardt, C., Adamantia Paizis, Pottschmidt, K., Sanchez-Fernandez, C., Wijnands, R., and High Energy Astrophys. & Astropart. Phys (API, FNWI) more...
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Astronomy - Abstract
The latest INTEGRAL Galactic Bulge monitoring (ATel #438) was performed during revolution 1529 on 2015 April 12 starting at 18:15 UT (57124.761 MJD) for a total of 12462 seconds.
318. 17 New Identified INTEGRAL Sources
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Loredana Bassani, Malizia, A., Stephen, J. B., Bazzano, A., Ubertini, P., Barlow, E. J., Bird, A. J., Dean, A. J., Hill, A. B., Shaw, S. E., Walter, R., Bodaghee, A., Belanger, G., Lebrun, F., Terrier, R., and Much, R. more...
319. Initial results from NuSTAR observations of the Norma Arm
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William W. Craig, Finn Erland Christensen, William W. Zhang, Charles J. Hailey, Fiona A. Harrison, Jaesub Hong, Kaya Mori, John A. Tomsick, Nicolas M. Barrière, Eric V. Gotthelf, Franz E. Bauer, Roman Krivonos, Steven E. Boggs, Arash Bodaghee, and Daniel Stern more...
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media_common.quotation_subject ,Cataclysmic variable star ,FOS: Physical sciences ,Norma Arm ,Astrophysics ,Magnetar ,01 natural sciences ,X-RAY SURVEY ,law.invention ,STAR-FORMATION ,Telescope ,general [binaries] ,neutron [stars] ,law ,0103 physical sciences ,novae, cataclysmic variables ,MAGNETIC CATACLYSMIC VARIABLES ,010303 astronomy & astrophysics ,media_common ,Line (formation) ,Physics ,High Energy Astrophysical Phenomena (astro-ph.HE) ,COMPLEX ,010308 nuclear & particles physics ,Star formation ,Galactic Center ,ASTRONOMY ,Astronomy and Astrophysics ,CATALOG ,Space and Planetary Science ,Sky ,binaries [X-rays] ,Astrophysics - High Energy Astrophysical Phenomena ,GALACTIC-CENTER - Abstract
Results are presented for an initial survey of the Norma Arm gathered with the focusing hard X-ray telescope NuSTAR. The survey covers 0.2 deg$^2$ of sky area in the 3-79 keV range with a minimum and maximum raw depth of 15 ks and 135 ks, respectively. Besides a bright black-hole X-ray binary in outburst (4U 1630-47) and a new X-ray transient (NuSTAR J163433-473841), NuSTAR locates three sources from the Chandra survey of this region whose spectra are extended above 10 keV for the first time: CXOU J163329.5-473332, CXOU J163350.9-474638, and CXOU J163355.1-473804. Imaging, timing, and spectral data from a broad X-ray range (0.3-79 keV) are analyzed and interpreted with the aim of classifying these objects. CXOU J163329.5-473332 is either a cataclysmic variable or a faint low-mass X-ray binary. CXOU J163350.9-474638 varies in intensity on year-long timescales, and with no multi-wavelength counterpart, it could be a distant X-ray binary or possibly a magnetar. CXOU J163355.1-473804 features a helium-like iron line at 6.7 keV and is classified as a nearby cataclysmic variable. Additional surveys are planned for the Norma Arm and Galactic Center, and those NuSTAR observations will benefit from the lessons learned during this pilot study., Comment: Accepted for publication in the Astrophysical Journal, 10 pages, 4 figures, 3 tables more...
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320. INTEGRAL detects the hard X-ray brightening of 4U 1630-47
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Bodaghee, A., Popp, A., Grinberg, V., Manousakis, A., Turler, M., Bozzo, E., Ferrigno, C., Tomsick, J. A., Duro, R., Hell, N., Miskovicova, I., Obst, M., Wilms, J., Lohfink, A., Marcu, D., Pottschmidt, K., Cadolle Bel, M., Kuulkers, E., Rodriguez, J., Krivonos, R., Chenevez, J., Adamantia Paizis, Kennea, J., Romano, P., Den Hartog, P. R., Barriere, N., Beckmann, V., and Soldi, S. more...
321. Outburst from the SFXT IGR J17544-2619 detected by INTEGRAL
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Adamantia Paizis, Kuulkers, E., Chenevez, J., Bazzano, A., Beckmann, V., Bird, T., Bodaghee, A., Del Santo, M., Domingo, A., Jonker, P., Kretschmar, P., Pottschmidt, K., Markwardt, C., Sanchez-Fernandez, C., Wijnands, R., and High Energy Astrophys. & Astropart. Phys (API, FNWI) more...
- Abstract
During public INTEGRAL Galactic bulge monitoring observations (ATel #438) performed on 2015 February 20-21 at UT 23:04-02:45, we detected the SFXT IGR J17544-2619 (see ATel #7137 for the recent Swift detection of the source outburst). more...
322. 14 New Unidentified INTEGRAL Sources
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Walter, R., Bodaghee, A., Barlow, E. J., Bird, A. J., Dean, A., Hill, A. B., Shaw, S., Bazzano, A., Ubertini, P., Bassani, L., Angela Malizia, Stephen, J. B., Belanger, G., Lebrun, F., and Terrier, R. more...
323. INTEGRAL detects XTE J1739-285
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Bodaghee, A., Mowlavi, N., Kuulkers, E., Wijnands, R., Shaw, S. E., Courvoisier, T., Markwardt, C., Oosterbroek, T., Orr, A., Paizis, A., Ebisawa, K., and Peter Kretschmar
324. INTEGRAL finds renewed X-ray activity of the Neutron star X-ray transient SAX J1750.8-2900
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Sanchez-Fernandez, Celia, Chenevez, Jerome, Kuulkers, Erik, Bazzano, Angela, Beckmann, Volker, Bird, Tony, Bodaghee, Arash, Del Santo, Melania, Domingo, Albert, Jonker, Peter, Kretschmar, Peter, Markwardt, Craig, Adamantia Paizis, Pottschmidt, Katja, Wijnands, Rudy, and High Energy Astrophys. & Astropart. Phys (API, FNWI) more...
- Subjects
Astronomy - Abstract
NTEGRAL Galactic bulge monitoring observations (ATel #438) on UT 13 September 2015 18:50-22:32 reveal renewed X-ray activity from the low-mass X-ray binary transient and Type I X-ray burster SAX J1750.8-2900 (IAU Circ. #6597). The last outburst from this source was reported in 2011 (ATels #3170, 3181). more...
325. Chandra provides new X-ray positions for IGR J16393-4643 and IGR J17091-3624
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Arash Bodaghee, Jerome Rodriguez, Farid Rahoui, and John A. Tomsick
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Physics ,X-ray ,Astrophysics
326. The Supergiant Fast X-ray Transient with the shortest orbital period: Suzaku observes one orbit in IGR J16479-4514
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Joern Wilms, Katja Pottschmidt, V. Sguera, L. Sidoli, P. Romano, Jerome Rodriguez, John A. Tomsick, Paolo Esposito, and Arash Bodaghee
- Subjects
Physics ,X-ray transient ,Astrophysics ,Orbit (control theory) ,Supergiant ,Orbital period
327. Scientific performance of the ISDC quick look analysis
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Shaw, S. E., Mowlavi, N., Ebisawa, K., Paizis, A., Rodriguez, J., Zurita, J., Walter, R., Türler, M., Soldan, J., Sauvageon, A., Produit, N., Pottschmidt, K., Meynis, P., Martins, L., Lerusse, L., Kreykenbohm, I., Kretschmar, P., Haymoz, P., Favre, P., Dubath, P., Deluit, S., Courvoisier, T. J. -L, Chernyakova, M., Bodaghee, A., and Volker Beckmann more...
- Subjects
Astrophysics (astro-ph) ,FOS: Physical sciences ,Astrophysics - Abstract
The INTEGRAL Science Data Centre (ISDC) routinely monitors the Near Real Time data (NRT) from the INTEGRAL satellite. A first scientific analysis is made in order to check for the detection of new, transient or highly variable sources in the data. Of primary importance for this work is the Interactive Quick Look Analysis (IQLA), which produces JEM-X and ISGRI images and monitors them for interesting astrophysical events, 4 pages, 3 figures. Proceedings of 5th INTEGRAL Workshop: The INTEGRAL Universe, Munich, 16-20 February 2004. Accepted for publication in European Space Agency Special Publication 552. See paper for institute affiliations more...
328. IGR J16393-4643 a possible X-ray counterpart to 3EG J1639-4702 discovered by INTEGRAL
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Malizia, A., Loredana Bassani, Di Cocco, G., Stephen, J. B., Walter, R., Bodaghee, A., and Bazzano, A.
329. GRS 1758-258 not detected at hard X-rays
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Pottschmidt, K., Eikmann, W., Kreykenbohm, I., Joern Wilms, Hirsch, M., Kuehnel, M., Rodrigues, B. H. G., Krauss, F., Soria, R., Grinberg, V., Smith, D. M., Cadolle Bel, M., Tomsick, J. A., Bodaghee, A., Kuulkers, E., Integral, Galactic Bulge Monitoring Team, Kalemci, E., and Miller, J. M. more...
330. INTEGRAL detection of a hard X-ray transient in NGC 6440
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Kuulkers, E., Bozzo, E., Bazzano, A., Beckmann, V., Bird, T., Bodaghee, A., Chenevez, J., Del Santo, M., Domingo, A., Jonker, P., Peter Kretschmar, Paizis, A., Pottschmidt, K., Markwardt, C., Sanchez-Fernandez, C., Wijnands, R., and High Energy Astrophys. & Astropart. Phys (API, FNWI) more...
- Abstract
During INTEGRAL Galactic bulge monitoring (e.g., ATel #438) observations performed on UT 2015 February 17 at 12.53-16:45, IBIS/ISGRI detected renewed activity at hard X-rays from a transient within the Globular Cluster NGC 6440. more...
331. Multi-wavelenght Observations of INTEGRAL sources & the parameter space occupied by soft γ-ray emitting objects
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Bodaghee, Arash and Bodaghee, Arash
- Abstract
Une vision synthétique des 500 sources détectées par INTEGRAL est présentée. Presque la moitié des sources étaient inconnues à ces énergies (>20 keV). Les études menées sur certains objets ont permis de les classifier comme des HMXBs composés d'étoiles à neutrons pulsantes qui agglomèrent le vent d'étoiles supergéantes. Ainsi, une nouvelle population de PULSARS enfouis a été mise en évidence. En moyenne, les IGRs galactiques sont 4 fois plus absorbées que les sources galactiques connues avant INTEGRAL. Des tendances non-négligeables ressortent des diagrammes Pulse-Absorption et Orbite-Absorption des HMXBs. Les populations de HMXBs OB et Be se séparent en des régions distinctes de ces diagrammes permettant de proposer une contrepartie à un HMXB qui est non-classifié. La distribution spatiale des HMXBs est compatible avec les complexes actifs en formation d'étoiles OB, et la rotation galactique n'améliore pas l'alignement entre les HMXBs et les bras spiraux. Les sources non identifiées ont une distribution spatiale qui rappelle celle des LMXBs. more...
332. INTEGRAL and XMM-Newton observations of the X-ray pulsar IGR J16320-4751/AX J1631.9-4752
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Rodriguez, J., Bodaghee, A., Kaaret, P., Tomsick, J.A., Kuulkers, E., Malaguti, G., Petrucci, P.-O, Cabanac, C., Chernyakova, M., Corbel, S., Deluit, S., di Cocco, G., Ebisawa, K., Goldwurm, A., Henri, G., Lebrun, F., Paizis, A., Walter, R., Foschini, L., Rodriguez, J., Bodaghee, A., Kaaret, P., Tomsick, J.A., Kuulkers, E., Malaguti, G., Petrucci, P.-O, Cabanac, C., Chernyakova, M., Corbel, S., Deluit, S., di Cocco, G., Ebisawa, K., Goldwurm, A., Henri, G., Lebrun, F., Paizis, A., Walter, R., and Foschini, L. more...
- Abstract
We report on observations of the X-ray pulsar IGR J16320-4751 (also known as AX J1631.9-4752) performed simultaneously with International Gamma-Ray Astrophysics Laboratory (INTEGRAL) and XMM-Newton. We refine the source position and identify the most likely infrared counterpart. Our simultaneous coverage allows us to confirm the presence of X-ray pulsations at ∼1300 s, that we detect above 20 keV with INTEGRAL for the first time. The pulse fraction is consistent with being constant with energy, which is compatible with a model of polar accretion by a pulsar. We study the spectral properties of IGR J16320-4751 during two major periods occurring during the simultaneous coverage with both satellites, namely a flare and a non-flare period. We detect the presence of a narrow 6.4 keV iron line in both periods. The presence of such a feature is typical of supergiant wind accretors such as Vela X-1 or GX 301-2. We inspect the spectral variations with respect to the pulse phase during the non-flare period, and show that the pulse is solely due to variations of the X-ray flux emitted by the source and not due to variations of the spectral parameters. Our results are therefore compatible with the source being a pulsar in a High Mass X-ray Binary. We detect a soft excess appearing in the spectra as a blackbody with a temperature of ∼0.07 keV. We discuss the origin of the X-ray emission in IGR J16320-4751: while the hard X-rays are likely the result of Compton emission produced in the close vicinity of the pulsar, based on energy argument we suggest that the soft excess is likely the emission by a collisionally energized cloud in which the compact object is embedded more...
333. Young Accreting Compact Objects in M31: The Combined Power of NuSTAR, Chandra, and Hubble.
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M. Lazzarini, A. E. Hornschemeier, B. F. Williams, D. Wik, N. Vulic, M. Yukita, A. Zezas, A. R. Lewis, M. Durbin, A. Ptak, A. Bodaghee, B. D. Lehmer, V. Antoniou, and T. Maccarone
- Subjects
ACCRETION (Astrophysics) ,COMPACT objects (Astronomy) ,HARD X-rays ,X-ray binaries ,STELLAR mass ,NEUTRON stars - Abstract
We present 15 high-mass X-ray binary (HMXB) candidates in the disk of M31 for which we are able to infer compact object type, spectral type of the donor star, and age using multiwavelength observations from NuSTAR, Chandra, and the Hubble Space Telescope. The hard X-ray colors and luminosities from NuSTAR permit the tentative classification of accreting X-ray binary systems by compact object type, distinguishing black hole from neutron star systems. We find hard-state black holes, pulsars, and non-magnetized neutron stars associated with optical point-source counterparts with similar frequency. We also find nine non-magnetized neutron stars coincident with globular clusters and an equal number of pulsars with and without point-source optical counterparts. We perform spectral energy distribution (SED) fitting for the most likely optical counterparts to the HMXB candidates, finding seven likely high-mass stars and one possible red helium-burning star. The remaining seven HMXB optical counterparts have poor SED fits, so their companion stars remain unclassified. Using published star formation histories, we find that the majority of HMXB candidates—X-ray sources with UV-bright point-source optical counterpart candidates—are found in regions with star formation bursts less than 50 Myr ago, and three are associated with young stellar ages (<10 Myr). This is consistent with similar studies of HMXB populations in the Magellanic Clouds, M33, NGC 300, and NGC 2403. [ABSTRACT FROM AUTHOR] more...
- Published
- 2018
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334. Galactic Sources Detected in the NuSTAR Serendipitous Survey.
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John A. Tomsick, George B. Lansbury, Farid Rahoui, Maïca Clavel, Francesca M. Fornasini, JaeSub Hong, James Aird, David M. Alexander, Arash Bodaghee, Jeng-Lun Chiu, Jonathan E. Grindlay, Charles J. Hailey, Fiona A. Harrison, Roman A. Krivonos, Kaya Mori, and Daniel Stern more...
- Published
- 2017
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335. The NuSTAR Hard X-Ray Survey of the Norma Arm Region.
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Francesca M. Fornasini, John A. Tomsick, JaeSub Hong, Eric V. Gotthelf, Franz Bauer, Farid Rahoui, Daniel Stern, Arash Bodaghee, Jeng-Lun Chiu, Maïca Clavel, Jesús Corral-Santana, Charles J. Hailey, Roman A. Krivonos, Kaya Mori, David M. Alexander, Didier Barret, Steven E. Boggs, Finn E. Christensen, William W. Craig, and Karl Forster more...
- Published
- 2017
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336. NuSTAR HARD X-RAY SURVEY OF THE GALACTIC CENTER REGION. II. X-RAY POINT SOURCES.
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JaeSub Hong, Kaya Mori, Charles J. Hailey, Melania Nynka, Shuo Zhang, Eric Gotthelf, Francesca M. Fornasini, Roman Krivonos, Franz Bauer, Kerstin Perez, John A. Tomsick, Arash Bodaghee, Jeng-Lun Chiu, Maïca Clavel, Daniel Stern, Jonathan E. Grindlay, David M. Alexander, Tsuguo Aramaki, Frederick K. Baganoff, and Didier Barret more...
- Subjects
GALACTIC center ,X-ray telescopes ,THERMAL plasmas ,X-ray binaries ,PULSARS - Abstract
We present the first survey results of hard X-ray point sources in the Galactic Center (GC) region by NuSTAR. We have discovered 70 hard (3–79 keV) X-ray point sources in a 0.6 deg region around Sgr A* with a total exposure of 1.7 Ms, and 7 sources in the Sgr B2 field with 300 ks. We identify clear Chandra counterparts for 58 NuSTAR sources and assign candidate counterparts for the remaining 19. The NuSTAR survey reaches X-ray luminosities of ∼4× and ∼8 × 10 erg s at the GC (8 kpc) in the 3–10 and 10–40 keV bands, respectively. The source list includes three persistent luminous X-ray binaries (XBs) and the likely run-away pulsar called the Cannonball. New source-detection significance maps reveal a cluster of hard (>10 keV) X-ray sources near the Sgr A diffuse complex with no clear soft X-ray counterparts. The severe extinction observed in the Chandra spectra indicates that all the NuSTAR sources are in the central bulge or are of extragalactic origin. Spectral analysis of relatively bright NuSTAR sources suggests that magnetic cataclysmic variables constitute a large fraction (>40%–60%). Both spectral analysis and logN–logS distributions of the NuSTAR sources indicate that the X-ray spectra of the NuSTAR sources should have kT > 20 keV on average for a single temperature thermal plasma model or an average photon index of Γ = 1.5–2 for a power-law model. These findings suggest that the GC X-ray source population may contain a larger fraction of XBs with high plasma temperatures than the field population. [ABSTRACT FROM AUTHOR] more...
- Published
- 2016
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337. NuSTAR DISCOVERY OF A CYCLOTRON LINE IN THE ACCRETING X-RAY PULSAR IGR J16393-4643.
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Arash Bodaghee, John A. Tomsick, Francesca M. Fornasini, Roman Krivonos, Daniel Stern, Kaya Mori, Farid Rahoui, Steven E. Boggs, Finn E. Christensen, William W. Craig, Charles J. Hailey, Fiona A. Harrison, and William W. Zhang more...
- Subjects
- *
X-rays , *CYCLOTRONS , *CATHODE rays , *IONIZING radiation , *VACUUM tubes - Abstract
The high-mass X-ray binary and accreting X-ray pulsar IGR J16393-4643 was observed by the Nuclear Spectroscope Telescope Array in the 3–79 keV energy band for a net exposure time of 50 ks. We present the results of this observation which enabled the discovery of a cyclotron resonant scattering feature with a centroid energy of keV. This allowed us to measure the magnetic field strength of the neutron star for the first time: B = (2.5 ± 0.1) × 1012 G. The known pulsation period is now observed at 904.0 ± 0.1 s. Since 2006, the neutron star has undergone a long-term spin-up trend at a rate of s s−1 (−0.6 s per year, or a frequency derivative of Hz s−1). In the power density spectrum, a break appears at the pulse frequency which separates the zero slope at low frequency from the steeper slope at high frequency. This addition of angular momentum to the neutron star could be due to the accretion of a quasi-spherical wind, or it could be caused by the transient appearance of a prograde accretion disk that is nearly in corotation with the neutron star whose magnetospheric radius is around 2 × 108 cm. [ABSTRACT FROM AUTHOR] more...
- Published
- 2016
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338. INTEGRAL discovers a population of persistent intrinsically absorbed super-giant High-Mass X-Ray Binaries.
- Author
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Walter, R., Zurita, J., Bassani, L., Bazzano, A., Bodaghee, A., Dean, A., Dubath, P., Parmar, A., Renaud, M., and Ubertini, P.
- Abstract
During the first year in operation, INTEGRAL has detected more than 28 new bright sources which emit the bulk of their emission above 10 keV. Follow-up observations of a subset of these sources in the X-ray band with XMM-Newton indicate that 80% of them are very strongly absorbed. More than half of these absorbed sources show strong pulsations with long periods ranging from 139 to 1300s, i.e., they are slow X-ray pulsars. Many of these new sources are super-giant high-mass X-ray binaries (HMXB) in which the stellar wind of the companion star is accreted onto the compact object. The large local absorption in these new sources can be understood if the compact objects are buried deep in their stellar winds. These new objects represent half of the population of active super-giant HMXB. [ABSTRACT FROM PUBLISHER] more...
- Published
- 2005
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339. The high energy X-ray probe (HEX-P): Resolving the nature of Sgr A* flares, compact object binaries and diffuse X-ray emission in the Galactic center and beyond.
- Author
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Mori, Kaya, Ponti, Gabriele, Bachetti, Matteo, Bodaghee, Arash, Grindlay, Jonathan, Jaesub Hong, Krivonos, Roman, Kuznetsova, Ekaterina, Mandel, Shifra, Rodriguez, Antonio, Stel, Giovanni, Shuo Zhang, Tong Bao, Bauer, Franz, Clavel, Maïca, Coughenour, Benjamin, García, Javier A., Gerber, Julian, Grefenstette, Brian, and Jaodand, Amruta more...
- Subjects
- *
X-ray binaries , *GALACTIC center , *WHITE dwarf stars , *PARTICLE acceleration , *NEUTRINO detectors , *SUPERMASSIVE black holes , *MOLECULAR clouds - Abstract
HEX-P is a probe-class mission concept that will combine high spatial resolution X-ray imaging (<10" FWHM) and broad spectral coverage (0.2-80 keV) with an effective area far superior to current facilities' (including XMM-Newton and NuSTAR). These capabilities will enable revolutionary new insights into a variety of important astrophysical problems. We present scientific objectives and simulations of HEX-P observations of the Galactic Center (GC) and Bulge. We demonstrate the unique and powerful capabilities of the HEX-P observatory for studying both X-ray point sources and diffuse X-ray emission. HEX-P will be uniquely equipped to explore a variety of major topics in Galactic astrophysics, allowing us to 1) investigate broad-band properties of X-ray flares emitted from the supermassive black hole (BH) at Sgr A* and probe the associated particle acceleration and emission mechanisms; 2) identify hard X-ray sources detected by NuSTAR and determine X-ray point source populations in different regions and luminosity ranges; 3) determine the distribution of compact object binaries in the nuclear star cluster and the composition of the Galactic Ridge X-ray emission; 4) identify X-ray transients and measure fundamental parameters such as black hole spin; 5) find hidden pulsars in the Galactic Center; 6) search for BH-OB binaries and hard X-ray flares from young stellar objects in young massive clusters; 7) measure white dwarf (WD) masses of magnetic CVs to deepen our understanding of CV evolution and the origin of white dwarf magnetic fields; 8) explore primary particle accelerators in the GC in synergy with future TeV and neutrino observatories; 9) map out cosmic-ray distributions by observing nonthermal X-ray filaments; 10) explore past X-ray outbursts from Sgr A* through X-ray reflection components from giant molecular clouds. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
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340. CHANDRA OBSERVATIONS OF EIGHT SOURCES DISCOVERED BY INTEGRAL.
- Author
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John A. Tomsick, Roman Krivonos, Qinan Wang, Arash Bodaghee, Sylvain Chaty, Farid Rahoui, Jerome Rodriguez, and Francesca M. Fornasini
- Subjects
ACTIVE galaxies ,GALAXIES ,WHITE dwarf stars ,COMPACT objects (Astronomy) ,STELLAR evolution - Abstract
We report on 0.3–10 keV observations with the Chandra X-ray Observatory of eight hard X-ray sources discovered within 8° of the Galactic plane by the International Gamma-ray Astrophysics Laboratory satellite. The short (∼5 ks) Chandra observations of the IGR source fields have yielded very likely identifications of X-ray counterparts for three of the IGR sources: IGR J14091–6108, IGR J18088–2741, and IGR J18381–0924. The first two have very hard spectra in the Chandra band that can be described by a power law with photon indices of Γ = 0.6 ± 0.4 and –, respectively (90% confidence errors are given), and both have a unique near-IR counterpart consistent with the Chandra position. IGR J14091–6108 also displays a strong iron line and a relatively low X-ray luminosity, and we argue that the most likely source type is a cataclysmic variable (CV), although we do not completely rule out the possibility of a high mass X-ray binary. IGR J18088–2741 has an optical counterpart with a previously measured 6.84 hr periodicity, which may be the binary orbital period. We also detect five cycles of a possible 800–950 s period in the Chandra light curve, which may be the compact object spin period. We suggest that IGR J18088–2741 is also most likely a CV. For IGR J18381–0924, the spectrum is intrinsically softer with , and it is moderately absorbed, N
H = (4 ± 1) × 1022 cm−2 . There are two near-IR sources consistent with the Chandra position, and they are both classified as galaxies, making it likely that IGR J18381–0924 is an active galactic nucleus. For the other five IGR sources, we provide lists of nearby Chandra sources, which may be used along with further observations to identify the correct counterparts, and we discuss the implications of the low inferred Chandra count rates for these five sources. [ABSTRACT FROM AUTHOR] more...- Published
- 2016
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341. SPECTRAL STATE DEPENDENCE OF THE 0.4–2 MEV POLARIZED EMISSION IN CYGNUS X-1 SEEN WITH INTEGRAL/IBIS, AND LINKS WITH THE AMI RADIO DATA.
- Author
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Jérôme Rodriguez, Victoria Grinberg, Philippe Laurent, Marion Cadolle Bel, Katja Pottschmidt, Guy Pooley, Arash Bodaghee, Jörn Wilms, and Christian Gouiffès
- Subjects
ACCRETION (Astrophysics) ,ACCRETION disks ,BLACK holes ,STARS ,CYGNUS (Constellation) - Abstract
Polarization of the keV hard tail of the microquasar Cygnus X-1 has been independently reported by INTEGRAL/Imager on Board the INTEGRAL Satellite (IBIS), and INTEGRAL/SPectrometer on INTEGRAL and interpreted as emission from a compact jet. These conclusions were, however, based on the accumulation of all INTEGRAL data regardless of the spectral state. We utilize additional INTEGRAL exposure accumulated until 2012 December, and include the AMI/Ryle (15 GHz) radio data in our study. We separate the observations into hard, soft, and intermediate/transitional states and detect radio emission from a compact jet in hard and intermediate states (IS), but not in the soft. The 10–400 keV INTEGRAL (JEM-X and IBIS) state resolved spectra are well modeled with thermal Comptonization and reflection components. We detect a hard tail in the 0.4–2 MeV range for the hard state only. We extract the state dependent polarigrams of Cyg X-1, which are all compatible with no or an undetectable level of polarization except in the 400–2000 keV range in the hard state where the polarization fraction is 75% ± 32% and the polarization angle 40.°0 ± 14.°3. An upper limit on the 0.4–2 MeV soft state polarization fraction is 70%. Due to the short exposure, we obtain no meaningful constraint for the IS. The likely detection of a keV polarized tail in the hard state, together with the simultaneous presence of a radio jet, reinforce the notion of a compact jet origin of the keV emission. [ABSTRACT FROM AUTHOR] more...
- Published
- 2015
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342. XIPE: the x-ray imaging polarimetry explorer
- Author
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den Herder, Jan-Willem A., Takahashi, Tadayuki, Bautz, Marshall, Soffitta, P., Bellazzini, R., Bozzo, E., Burwitz, V., Castro-Tirado, A., Costa, E., Courvoisier, T., Feng, H., Gburek, S., Goosmann, R., Karas, V., Matt, G., Muleri, F., Nandra, K., Pearce, M., Poutanen, J., Reglero, V., Sabau Maria, D., Santangelo, A., Tagliaferri, G., Tenzer, C., Vink, J., Weisskopf, M. C., Zane, S., Agudo, I., Antonelli, A., Attina, P., Baldini, L., Bykov, A., Carpentiero, R., Cavazzuti, E., Churazov, E., Del Monte, E., De Martino, D., Donnarumma, I., Doroshenko, V., Evangelista, Y., Ferreira, I., Gallo, E., Grosso, N., Kaaret, P., Kuulkers, E., Laranaga, J., Latronico, L., Lumb, D. H., Macian, J., Malzac, J., Marin, F., Massaro, E., Minuti, M., Mundell, C., Ness, J. U., Oosterbroek, T., Paltani, S., Pareschi, G., Perna, R., Petrucci, P.-O., Pinazo, H. B., Pinchera, M., Rodriguez, J. P., Roncadelli, M., Santovincenzo, A., Sazonov, S., Sgro, C., Spiga, D., Svoboda, J., Theobald, C., Theodorou, T., Turolla, R., Wilhelmi de Ona, E., Winter, B., Akbar, A. M., Allan, H., Aloisio, R., Altamirano, D., Amati, L., Amato, E., Angelakis, E., Arezu, J., Atteia, J.-L., Axelsson, M., Bachetti, M., Ballo, L., Balman, S., Bandiera, R., Barcons, X., Basso, S., Baykal, A., Becker, W., Behar, E., Beheshtipour, B., Belmont, R., Berger, E., Bernardini, F., Bianchi, S., Bisnovatyi-Kogan, G., Blasi, P., Blay, P., Bodaghee, A., Boer, M., Boettcher, M., Bogdanov, S., Bombaci, I., Bonino, R., Braga, J., Brandt, W., Brez, A., Bucciantini, N., Burderi, L., Caiazzo, I., and Campana, R. more...
- Published
- 2016
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343. THE NORMA ARM REGION CHANDRA SURVEY CATALOG: X-RAY POPULATIONS IN THE SPIRAL ARMS.
- Author
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Fornasini, Francesca M., Tomsick, John A., Bodaghee, Arash, Krivonos, Roman A., An, Hongjun, Rahoui, Farid, Gotthelf, Eric V., Bauer, Franz E., and Stern, Daniel
- Subjects
X-ray astronomy ,ASTRONOMY ,SPACE astronomy ,X-rays ,CLASSIFICATION - Abstract
We present a catalog of 1415 X-ray sources identified in the Norma Arm Region Chandra Survey (NARCS), which covers a 2° × 0.°8 region in the direction of the Norma spiral arm to a depth of ≈20 ks. Of these sources, 1130 are point-like sources detected with ⩾3σ confidence in at least one of three energy bands (0.5-10, 0.5-2, and 2-10 keV), five have extended emission, and the remainder are detected at low significance. Since most sources have too few counts to permit individual classification, they are divided into five spectral groups defined by their quantile properties. We analyze stacked spectra of X-ray sources within each group, in conjunction with their fluxes, variability, and infrared counterparts, to identify the dominant populations in our survey. We find that ∼50% of our sources are foreground sources located within 1-2 kpc, which is consistent with expectations from previous surveys. Approximately 20% of sources are likely located in the proximity of the Scutum-Crux and near Norma arm, while 30% are more distant, in the proximity of the far Norma arm or beyond. We argue that a mixture of magnetic and nonmagnetic cataclysmic variables dominates the Scutum-Crux and near Norma arms, while intermediate polars and high-mass stars (isolated or in binaries) dominate the far Norma arm. We also present the cumulative number count distribution for sources in our survey that are detected in the hard energy band. A population of very hard sources in the vicinity of the far Norma arm and active galactic nuclei dominate the hard X-ray emission down to f
X ≈ 10–14 erg cm–2 s–1 , but the distribution curve flattens at fainter fluxes. We find good agreement between the observed distribution and predictions based on other surveys. [ABSTRACT FROM AUTHOR] more...- Published
- 2014
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344. INVESTIGATING THE OPTICAL COUNTERPART CANDIDATES OF FOUR INTEGRAL SOURCES LOCALIZED WITH CHANDRA.
- Author
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Özbey Arabacı, Mehtap, Kalemci, Emrah, Tomsick, John A., Halpern, Jules, Bodaghee, Arash, Chaty, Sylvain, Rodriguez, Jerome, and Rahoui, Farid
- Subjects
OPTICAL spectroscopy ,SOLAR flares ,SOLAR activity ,SOLAR radiation ,STARS - Abstract
We report on the optical spectroscopic follow-up observations of the candidate counterparts to four INTEGRAL sources: IGR J04069+5042, IGR J06552–1146, IGR J21188+4901, and IGR J22014+6034. The candidate counterparts were determined with Chandra, and the optical observations were performed with 1.5 m RTT-150 telescope (TÜBİTAK National Observatory, Antalya, Turkey) and 2.4 m Hiltner Telescope (MDM Observatory, Kitt Peak, Arizona). Our spectroscopic results show that one of the two candidates of IGR J04069+5042 and the one observed for IGR J06552–1146 could be active late-type stars in RS CVn systems. However, according to the likelihood analysis based on Chandra and INTEGRAL, two optically weaker sources in the INTEGRAL error circle of IGR J06552–1146 have higher probabilities to be the actual counterpart. The candidate counterparts of IGR J21188+4901 are classified as an active M-type star and a late-type star. Among the optical spectra of four candidates of IGR J22014+6034, two show Hα emission lines, one is a late-type star, and the other is an M type. The likelihood analysis favors a candidate with no distinguishing features in the optical spectrum. Two of the candidates classified as M-type dwarfs, are similar to some IGR candidates claimed to be symbiotic stars. However, some of the prominent features of symbiotic systems are missing in our spectra, and their NIR colors are not consistent with those expected for giants. We consider the IR colors of all IGR candidates claimed to be symbiotic systems and find that low-resolution optical spectrum may not be enough for conclusive identification. [ABSTRACT FROM AUTHOR] more...
- Published
- 2012
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345. XMM-NEWTON OBSERVATIONS OF FIVE INTEGRAL SOURCES LOCATED TOWARD THE SCUTUM ARM.
- Author
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Bodaghee, A., Tomsick, J. A., and Rodriguez, J.
- Subjects
- *
ACCRETION disks , *NEUTRON stars , *X-ray binaries , *ACCRETION (Astrophysics) - Abstract
Results are presented for XMM-Newton observations of five hard X-ray sources discovered by INTEGRAL in the direction of the Scutum Arm. Each source received ≳20 ks of effective exposure time. We provide refined X-ray positions for all five targets enabling us to pinpoint the most likely counterpart in optical/infrared archives. Spectral and timing information (much of which is provided for the first time) allow us to give a firm classification for IGR J18462–0223 and to offer tentative classifications for the others. For IGR J18462–0223, we discovered a coherent pulsation period of 997 ± 1 s, which we attribute to the spin of a neutron star in a highly obscured (NH =2 × 1023 cm–2) high-mass X-ray binary (HMXB). This makes IGR J18462–0223 the seventh supergiant fast X-ray transient candidate with a confirmed pulsation period. IGR J18457+0244 is a highly absorbed (NH =8 × 1023 cm–2) source in which the possible detection of an iron line suggests an active galactic nucleus (AGN) of type Sey-2 situated at z = 0.07(1). A periodic signal at 4.4 ks could be a quasi-periodic oscillation which would make IGR J18457+0244 one of a handful of AGNs in which such features have been claimed, but a slowly rotating neutron star in an HMXB cannot be ruled out. IGR J18482+0049 represents a new obscured HMXB candidate with NH =4 × 1023 cm–2. We tentatively propose that IGR J18532+0416 is either an AGN or a pulsar in an HMXB system. The X-ray spectral properties of IGR J18538–0102 are consistent with the AGN classification that has been proposed for this source. [ABSTRACT FROM AUTHOR] more...
- Published
- 2012
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346. CHANDRA OBSERVATIONS OF FIVE INTEGRAL SOURCES: NEW X-RAY POSITIONS FOR IGR J16393–4643 AND IGR J17091–3624.
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Bodaghee, A., Rahoui, F., Tomsick, J. A., and Rodriguez, J.
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ACCRETION (Astrophysics) , *ACCRETION disks , *NEUTRONS , *BINARY stars , *ASTROPHYSICS research - Abstract
The Chandra High Resolution Camera observed the fields of five hard X-ray sources in order to help us obtain X-ray coordinates with subarcsecond precision. These observations provide the most accurate X-ray positions known for IGR J16393–4643 and IGR J17091–3624. The obscured X-ray pulsar IGR J16393–4643 lies at R.A. (J2000) = 16h39m05.ˢ47, and decl. = –46°42′13.″0 (error radius of 0.″6 at 90% confidence). This position is incompatible with the previously proposed counterpart 2MASS J16390535–4642137, and it points instead to a new counterpart candidate that is possibly blended with the Two Micron All Sky Survey star. The black hole candidate IGR J17091–3624 was observed during its 2011 outburst providing coordinates of R.A. = 17h09m07.ˢ59, and decl. = –36°24′25.″4. This position is compatible with those of the proposed optical/IR and radio counterparts, solidifying the source's status as a microquasar. Three targets, IGR J14043–6148, IGR J16358–4726, and IGR J17597–2201, were not detected. We obtained 3σ upper limits of, respectively, 1.7, 1.8, and 1.5 × 10–12 erg cm–2 s–1 on their 2-10 keV fluxes. [ABSTRACT FROM AUTHOR] more...
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- 2012
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347. SUZAKU OBSERVES WEAK FLARES FROM IGR J17391–3021 REPRESENTING A COMMON LOW-ACTIVITY STATE IN THIS SUPERGIANT FAST X-RAY TRANSIENT.
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Bodaghee, A., Tomsick, J. A., Rodriguez, J., Chaty, S., Pottschmidt, K., Walter, R., and Romano, P.
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- 2011
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348. Chandra, NuSTAR, and Optical Observations of the Cataclysmic Variables IGR J17528-2022 and IGR J20063+3641.
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Hare, Jeremy, Halpern, Jules P., Tomsick, John A., Thorstensen, John R., Bodaghee, Arash, Clavel, Maďca, Krivonos, Roman, and Mori, Kaya
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OPTICAL spectra , *LIGHT sources , *ASTROPHYSICS , *BREMSSTRAHLUNG , *PHOTOMETRY , *ASTRONOMICAL photometry - Abstract
We report on Chandra, NuSTAR, and MDM observations of two International Gamma-ray Astrophysics Laboratory (INTEGRAL) sources, namely IGR J17528−2022 and IGR J20063+3641. IGR J17528−2022 is an unidentified INTEGRAL source, while IGR J20063+3641 was recently identified as a magnetic cataclysmic variable (mCV) by Halpern et al. The Chandra observation of IGR J17528−2022 has allowed us to locate the optical counterpart to the source and to obtain its optical spectrum, which shows a strong Hα emission line. The optical spectrum and flickering observed in the optical time-series photometry in combination with the X-ray spectrum, which is well fit by an absorbed partially covered thermal bremsstrahlung model, suggest that this source is a strong mCV candidate. The X-ray observations of IGR J20063+3641 reveal a clear modulation with a period of 172.46 ± 0.01 s, which we attribute to the white dwarf spin period. Additional MDM spectroscopy of the source has also allowed for a clear determination of the orbital period at 0.731 ± 0.015 days. The X-ray spectrum of this source is also well fit by an absorbed partially covered thermal bremsstrahlung model. The X-ray spectrum, spin periodicity, and orbital periodicity allow this source to be further classified as an intermediate polar. [ABSTRACT FROM AUTHOR] more...
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- 2021
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349. Using Chandra Localizations and Gaia Distances and Proper Motions to Classify Hard X-Ray Sources Discovered by INTEGRAL.
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Tomsick, John A., Coughenour, Benjamin M., Hare, Jeremy, Krivonos, Roman, Bodaghee, Arash, Chaty, Sylvain, Clavel, Maďca, Fornasini, Francesca M., Rodriguez, Jerome, and Shaw, Aarran W.
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HARD X-rays , *X-ray binaries , *ACTIVE galactic nuclei , *DISTANCES , *ASTROPHYSICS - Abstract
Here, we report on X-ray observations of ten 17–60 keV sources discovered by the International Gamma-Ray Astrophysics Laboratory satellite. The primary new information is sub-arcsecond positions obtained by the Chandra X-ray Observatory. In six cases (IGR J17040-4305, IGR J18017-3542, IGR J18112-2641, IGR J18434-0508, IGR J19504+3318, and IGR J20084+3221), a unique Chandra counterpart is identified with a high degree of certainty, and for five of these sources (all but J19504), Gaia distances or proper motions indicate that they are Galactic sources. For four of these, the most likely classifications are that the sources are magnetic cataclysmic variables (CVs). J20084 could be either a magnetic CV or a high-mass X-ray binary. We classify the sixth source (J19504) as a likely active galactic nucleus (AGN). In addition, we find likely Chandra counterparts to IGR J18010-3045 and IGR J19577+3339, and the latter is a bright radio source and probable AGN. The other two sources, IGR J12529-6351 and IGR J18013-3222, do not have likely Chandra counterparts, indicating that they are transient, highly variable, or highly absorbed. [ABSTRACT FROM AUTHOR] more...
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- 2021
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350. 15 years of galactic surveys and hard X-ray background measurements.
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Krivonos, Roman A., Bird, Antony J., Churazov, Eugene M., Tomsick, John A., Bazzano, Angela, Beckmann, Volker, Bélanger, Guillaume, Bodaghee, Arash, Chaty, Sylvain, Kuulkers, Erik, Lutovinov, Alexander, Malizia, Angela, Masetti, Nicola, Mereminskiy, Ilya A., Sunyaev, Rashid, Tsygankov, Sergey S., Ubertini, Pietro, and Winkler, Christoph more...
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HARD X-rays , *X-ray astronomy , *X-ray telescopes , *GRAZING incidence , *RADIO frequency , *COSMIC rays , *COSMIC background radiation - Abstract
The INTEGRAL hard X-ray surveys have proven to be of fundamental importance. INTEGRAL has mapped the Galactic plane with its large field of view and excellent sensitivity. Such hard X-ray snapshots of the whole Milky Way on a time scale of a year are beyond the capabilities of past and current narrow-FOV grazing incidence X-ray telescopes. By expanding the INTEGRAL X-ray survey into shorter timescales, a productive search for transient X-ray emitters was made possible. In more than fifteen years of operation, the INTEGRAL observatory has given us a sharper view of the hard X-ray sky, and provided the triggers for many follow-up campaigns from radio frequencies to gamma-rays. In addition to conducting a census of hard X-ray sources across the entire sky, INTEGRAL has carried out, through Earth occultation manoeuvres, unique observations of the large-scale cosmic X-ray background, which will without question be included in the annals of X-ray astronomy as one of the mission's most salient contribution to our understanding of the hard X-ray sky. [ABSTRACT FROM AUTHOR] more...
- Published
- 2021
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