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

Author

Pelliciari, D., Bernardi, G., Pilia, M., Naldi, G., Maccaferri, G., Verrecchia, F., Casentini, C., Perri, M., Kirsten, F., Bianchi, G., Bortolotti, C., Bruno, L., Dallacasa, D., Esposito, P., Geminardi, A., Giarratana, S., Giroletti, M., Lulli, R., Maccaferri, A., Magro, A., Mattana, A., Perini, F., Pupillo, G., Roma, M., Schiaffino, M., Setti, G., Tavani, M., Trudu, M., and Zanichelli, A.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

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 the FRB population have shown repeating bursts, however it's still unclear whether these represent a distinct class of sources. We investigated the bursting behaviour of FRB 20220912A, one of the most active repeating FRBs known thus far. In particular, we focused on its burst energy distribution, linked to the source energetics, and its emission spectrum, with the latter directly related to the underlying emission mechanism. We monitored FRB 20220912A at $408$ MHz with the Northern Cross radio telescope and at $1.4$ GHz using the $32$-m Medicina Grueff radio telescope. Additionally, we conducted $1.2$ GHz observations taken with the upgraded Giant Meter Wave Radio Telescope (uGMRT) searching for a persistent radio source coincident with FRB 20220912A, which included high energy observations in the $0.3-10$ keV, $0.4-100$ MeV and $0.03-30$ GeV energy range. We report $16$ new bursts from FRB 20220912A at $408$ MHz during the period between October 16$^{\rm th}$ 2022 and December 31$^{\rm st}$ 2023. Their cumulative spectral energy distribution follows a power law with slope $\alpha_E = -1.3 \pm 0.2$ and we measured a repetition rate of $0.19 \pm 0.03$ hr$^{-1}$ for bursts having a fluence of $\mathcal{F} \geq 17$ Jy ms. Furthermore, we report no detections at 1.4 GHz for $\mathcal{F} \geq 20$ Jy ms. These non-detections imply an upper limit of $\beta < -2.3$, with $\beta$ being the $408$ MHz $-$ $1.4$ GHz spectral index of FRB 20220912A. This is inconsistent with positive $\beta$ values found for the only two known cases in which an FRB has been detected in separate spectral bands. We find that FRB 20220912A shows a decline of four orders of magnitude in its bursting activity at $1.4$ GHz over a .. (abridged), Comment: accepted for publication, 13 pages, 4 figures

Published
2024
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2. The ground calibration of the HERMES-Pathfinder payload flight models

Author

Dilillo, G., Marchesini, E. J., Baroni, G., Della Casa, G., Campana, R., Evangelista, Y., Guzmán, A., Hedderman, P., Bellutti, P., Bertuccio, G., Ceraudo, F., Citossi, M., Cirrincione, D., Dedolli, I., Demenev, E., Feroci, M., Ficorella, F., Fiorini, M., Gandola, M., Grassi, M., Rosa, G. La, Lombardi, G., Malcovati, P., Mele, F., Nogara, P., Nuti, A., Perri, M., Pliego-Caballero, S., Pirrotta, S., Puccetti, S., Rashevskaya, I., Russo, F., Sottile, G., Tenzer, C., Trenti, M., Trevisan, S., Vacchi, A., Zampa, G., Zampa, N., and Fiore, F.

Published
2024
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3. Swift and NuSTAR observations of GW170817: detection of a blue kilonova

Author

Evans, P. A., Cenko, S. B., Kennea, J. A., Emery, S. W. K., Kuin, N. P. M., Korobkin, O., Wollaeger, R. T., Fryer, C. L., Madsen, K. K., Harrison, F. A., Xu, Y., Nakar, E., Hotokezaka, K., Lien, A., Campana, S., Oates, S. R., Troja, E., Breeveld, A. A., Marshall, F. E., Barthelmy, S. D., Beardmore, A. P., Burrows, D. N., Cusumano, G., D'Ai, A., D'Avanzo, P., D'Elia, V., de Pasquale, M., Even, W. P., Fontes, C. J., Forster, K., Garcia, J., Giommi, P., Grefenstette, B., Gronwall, C., Hartmann, D. H., Heida, M., Hungerford, A. L., Kasliwal, M. M., Krimm, H. A., Levan, A. J., Malesani, D., Melandri, A., Miyasaka, H., Nousek, J. A., O'Brien, P. T., Osborne, J. P., Pagani, C., Page, K. L., Palmer, D. M., Perri, M., Pike, S., Racusin, J. L., Rosswog, S., Siegel, M. H., Sakamoto, T., Sbarufatti, B., Tagliaferri, G., Tanvir, N. R., and Tohuvavohu, A.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

With the first direct detection of merging black holes in 2015, the era of gravitational wave (GW) astrophysics began. A complete picture of compact object mergers, however, requires the detection of an electromagnetic (EM) counterpart. We report ultraviolet (UV) and X-ray observations by Swift and the Nuclear Spectroscopic Telescope ARray (NuSTAR) of the EM counterpart of the binary neutron star merger GW170817. The bright, rapidly fading ultraviolet emission indicates a high mass ($\approx0.03$ solar masses) wind-driven outflow with moderate electron fraction ($Y_{e}\approx0.27$). Combined with the X-ray limits, we favor an observer viewing angle of $\approx 30^{\circ}$ away from the orbital rotation axis, which avoids both obscuration from the heaviest elements in the orbital plane and a direct view of any ultra-relativistic, highly collimated ejecta (a gamma-ray burst afterglow)., Comment: Science, in press; 56 pages, 12 figures

Published
2017
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4. Online Data Generation in Quantitative Analysis: Excel Spreadsheets and an Online HPLC Simulator Using a Jupyter Notebook on the Chem Compute Web Site

Author

Perri, M. J.

Abstract

Students used an Excel spreadsheet and a Jupyter notebook located at https://chemcompute.org/jupyterhub/ to generate data in lieu of face-to-face laboratory instruction during COVID-19. This communication discusses strengths and weaknesses of both exercises. First, students generated absorbance data using an Excel spreadsheet, but they were overwhelmingly put off by simulated noise in their absorbance values. Second, students simulated running an HPLC using a Jupyter notebook and designed a method to separate three components of Excedrin. Students reported that the simulation helped them to understand HPLC and suggested that the online activity be used as a supplement when face-to-face laboratory instruction resumes. The main weakness of the online activities was that students did not perform any sample preparation. Therefore, they did not experience the extractions and dilutions required to prepare the analytical sample and had a difficult time working backward to calculate starting amounts from simulated sample concentrations. Concerns that students would extract answers from the equations used in the spreadsheet and Jupyter notebook were not realized.

Published
2020
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6. Design, construction, and test of the Gas Pixel Detectors for the IXPE mission

Author

Baldini, L., Barbanera, M., Bellazzini, R., Bonino, R., Borotto, F., Brez, A., Caporale, C., Cardelli, C., Castellano, S., Ceccanti, M., Citraro, S., Di Lalla, N., Latronico, L., Lucchesi, L., Magazzù, C., Magazzù, G., Maldera, S., Manfreda, A., Marengo, M., Marrocchesi, A., Mereu, P., Minuti, M., Mosti, F., Nasimi, H., Nuti, A., Oppedisano, C., Orsini, L., Pesce-Rollins, M., Pinchera, M., Profeti, A., Sgrò, C., Spandre, G., Tardiola, M., Zanetti, D., Amici, F., Andersson, H., Attinà, P., Bachetti, M., Baumgartner, W., Brienza, D., Carpentiero, R., Castronuovo, M., Cavalli, L., Cavazzuti, E., Centrone, M., Costa, E., D’Alba, E., D’Amico, F., Del Monte, E., Di Cosimo, S., Di Marco, A., Di Persio, G., Donnarumma, I., Evangelista, Y., Fabiani, S., Ferrazzoli, R., Kitaguchi, T., La Monaca, F., Lefevre, C., Loffredo, P., Lorenzi, P., Mangraviti, E., Matt, G., Meilahti, T., Morbidini, A., Muleri, F., Nakano, T., Negri, B., Nenonen, S., O’Dell, S.L., Perri, M., Piazzolla, R., Pieraccini, S., Pilia, M., Puccetti, S., Ramsey, B.D., Rankin, J., Ratheesh, A., Rubini, A., Santoli, F., Sarra, P., Scalise, E., Sciortino, A., Soffitta, P., Tamagawa, T., Tennant, A.F., Tobia, A., Trois, A., Uchiyama, K., Vimercati, M., Weisskopf, M.C., Xie, F., Zanetti, F., and Zhou, Y.

Published
2021
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7. Multiband variability studies and novel broadband SED modeling of Mrk 501 in 2009

Author

Ahnen, M. L., Ansoldi, S., Antonelli, L. A., Antoranz, P., Babic, A., Banerjee, B., Bangale, P., de Almeida, U. Barres, Barrio, J. A., González, J. Becerra, Bednarek, W., Bernardini, E., Berti, A., Biasuzzi, B., Biland, A., Blanch, O., Bonnefoy, S., Bonnoli, G., Borracci, F., Bretz, T., Buson, S., Carosi, A., Chatterjee, A., Clavero, R., Colin, P., Colombo, E., Contreras, J. L., Cortina, J., Covino, S., Da Vela, P., Dazzi, F., De Angelis, A., De Lotto, B., Wilhelmi, E. de Ona, Di Pierro, F., Doert, M., Domínguez, A., Prester, D. Dominis, Dorner, D., Doro, M., Einecke, S., Glawion, D. Eisenacher, Elsaesser, D., Engelkemeier, M., Ramazani, V. Fallah, Fernández-Barral, A., Fidalgo, D., Fonseca, M. V., Font, L., Frantzen, K., Fruck, C., Galindo, D., López, R. J. García, Garczarczyk, M., Terrats, D. Garrido, Gaug, M., Giammaria, P., Godinović, N., Munoz, A. González, Gora, D., Guberman, D., Hadasch, D., Hahn, A., Hanabata, Y., Hayashida, M., Herrera, J., Hose, J., Hrupec, D., Hughes, G., Idec, W., Kodani, K., Konno, Y., Kubo, H., Kushida, J., La Barbera, A., Lelas, D., Lindfors, E., Lombardi, S., Longo, F., López, M., López-Coto, R., Majumdar, P., Makariev, M., Mallot, K., Maneva, G., Manganaro, M., Mannheim, K., Maraschi, L., Marcote, B., Mariotti, M., Martínez, M., Mazin, D., Menzel, U., Miranda, J. M., Mirzoyan, R., Moralejo, A., Moretti, E., Nakajima, D., Neustroev, V., Niedzwiecki, A., Rosillo, M. Nievas, Nilsson, K., Nishijima, K., Noda, K., Nogués, L., Overkemping, A., Paiano, S., Palacio, J., Palatiello, M., Paneque, D., Paoletti, R., Paredes, J. M., Paredes-Fortuny, X., Pedaletti, G., Peresano, M., Perri, L., Persic, M., Poutanen, J., Moroni, P. G. Prada, Prandini, E., Puljak, I., Reichardt, I., Rhode, W., Ribó, M., Rico, J., Garcia, J. Rodriguez, Saito, T., Satalecka, K., Schröder, S., Schultz, C., Schweizer, T., Shore, S. N., Sillanpää, A., Sitarek, J., Snidaric, I., Sobczynska, D., Stamerra, A., Steinbring, T., Strzys, M., Surić, T., Takalo, L., Tavecchio, F., Temnikov, P., Terzić, T., Tescaro, D., Teshima, M., Thaele, J., Torres, D. F., Toyama, T., Treves, A., Vanzo, G., Verguilov, V., Vovk, I., Ward, J. E., Will, M., Wu, M. H., Zanin, R., Abeysekara, A. U., Archambault, S., Archer, A., Benbow, W., Bird, R., Buchovecky, M., Buckley, J. H., Bugaev, V., Connolly, M. P., Cui, W., Dickinson, H. J., Falcone, A., Feng, Q., Finley, J. P., Fleischhack, H., Flinders, A., Fortson, L., Gillanders, G. H., Griffin, S., Grube, J., Hütten, M., Hanna, D., Holder, J., Humensky, T. B., Kaaret, P., Kar, P., Kelley-Hoskins, N., Kertzman, M., Kieda, D., Krause, M., Krennrich, F., Lang, M. J., Maier, G., McCann, A., Moriarty, P., Mukherjee, R., Nieto, D., O'Brien, S., Ong, R. A., Otte, N., Park, N., Perkins, J., Pichel, A., Pohl, M., Popkow, A., Pueschel, E., Quinn, J., Ragan, K., Reynolds, P. T., Richards, G. T., Roache, E., Rovero, A. C., Rulten, C., Sadeh, I., Santander, M., Sembroski, G. H., Shahinyan, K., Telezhinsky, I., Tucci, J. V., Tyler, J., Wakely, S. P., Weinstein, A., Wilcox, P., Wilhelm, A., Williams, D. A., Zitzer, B., Razzaque, S., Villata, M., Raiteri, C. M., Aller, H. D., Aller, M. F., Larionov, V. M., Arkharov, A. A., Blinov, D. A., Efimova, N. V., Grishina, T. S., Hagen-Thorn, V. A., Kopatskaya, E. N., Larionova, L. V., Larionova, E. G., Morozova, D. A., Troitsky, I. S., Ligustri, R., Calcidese, P., Berdyugin, A., Kurtanidze, O. M., Nikolashvili, M. G., Kimeridze, G. N., Sigua, L. A., Kurtanidze, S. O., Chigladze, R. A., Chen, W. P., Koptelova, E., Sakamoto, T., Sadun, A. C., Moody, J. W., Pace, C., Pearson III, R., Yatsu, Y., Mori, Y., Carraminyana, A., Carrasco, L., de la Fuente, E., Norris, J. P., Smith, P. S., Wehrle, A., Gurwell, M. A., Zook, Alma, Pagani, C., Perri, M., Capalbi, M., Cesarini, A., Krimm, H. A., Kovalev, Y. Y., Kovalev, Yu. A., Ros, E., Pushkarev, A. B., Lister, M. L., Sokolovsky, K. V., Kadler, M., Piner, G., Lähteenmäki, A., Tornikoski, M., Angelakis, E., Krichbaum, T. P., Nestoras, I., Fuhrmann, L, Zensus, J. A., Cassaro, P., Orlati, A., Maccaferri, G., Leto, P., Giroletti, M., Richards, J. L., Max-Moerbeck, W., and Readhead, A. C. S.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

We present an extensive study of the BL Lac object Mrk 501 based on a data set collected during the multi-instrument campaign spanning from 2009 March 15 to 2009 August 1 which includes, among other instruments, MAGIC, VERITAS, Whipple 10-m, Fermi-LAT, RXTE, Swift, GASP-WEBT and VLBA. We find an increase in the fractional variability with energy, while no significant interband correlations of flux changes are found in the acquired data set. The higher variability in the very high energy (>100 GeV, VHE) gamma-ray emission and the lack of correlation with the X-ray emission indicate that the highest-energy electrons that are responsible for the VHE gamma-rays do not make a dominant contribution to the ~1 keV emission. Alternatively, there could be a very variable component contributing to the VHE gamma-ray emission in addition to that coming from the synchrotron self-Compton (SSC) scenarios. The space of SSC model parameters is probed following a dedicated grid-scan strategy, allowing for a wide range of models to be tested and offering a study of the degeneracy of model-to-data agreement in the individual model parameters. We find that there is some degeneracy in both the one-zone and the two-zone SSC scenarios that were probed, with several combinations of model parameters yielding a similar model-to-data agreement, and some parameters better constrained than others. The SSC model grid-scan shows that the flaring activity around 2009 May 22 cannot be modeled adequately with a one-zone SSC scenario, while it can be suitably described within a two-independent-zone SSC scenario. The observation of an electric vector polarization angle rotation coincident with the gamma-ray flare from 2009 May 1 resembles those reported previously for low frequency peaked blazars, hence suggesting that there are many similarities in the flaring mechanisms of blazars with different jet properties., Comment: 33 pages, 15 figures, accepted for publication in A&A. Corresponding authors: Marlene Doert (marlene.doert@tu-dortmund.de) and David Paneque (dpaneque@mppmu.mpg.de)

Published
2016
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8. An accreting pulsar with extreme properties drives an ultraluminous x-ray source in NGC 5907

Author

Israel, G. L., Belfiore, A., Stella, L., Esposito, P., Casella, P., De Luca, A., Marelli, M., Papitto, A., Perri, M., Puccetti, S., Castillo, G. A. Rodriguez, Salvetti, D., Tiengo, A., Zampieri, L., D'Agostino, D., Greiner, J., Haberl, F., Novara, G., Salvaterra, R., Turolla, R., Watson, M., Wilms, J., and Wolter, A.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

Ultraluminous x-ray sources (ULXs) in nearby galaxies shine brighter than any X-ray source in our Galaxy. ULXs are usually modeled as stellar-mass black holes (BHs) accreting at very high rates or intermediate-mass BHs. We present observations showing that NGC5907 ULX is instead an x-ray accreting neutron star (NS) with a spin period evolving from 1.43~s in 2003 to 1.13~s in 2014. It has an isotropic peak luminosity of about 1000 times the Eddington limit for a NS at 17.1~Mpc. Standard accretion models fail to explain its luminosity, even assuming beamed emission, but a strong multipolar magnetic field can describe its properties. These findings suggest that other extreme ULXs (x-ray luminosity > 10^{41} erg/s) might harbor NSs., Comment: 37 pages including Supplementary Material; 7 figures

Published
2016
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9. An X-ray burst from a magnetar enlightening the mechanism of fast radio bursts

Author

Tavani, M., Casentini, C., Ursi, A., Verrecchia, F., Addis, A., Antonelli, L. A., Argan, A., Barbiellini, G., Baroncelli, L., Bernardi, G., Bianchi, G., Bulgarelli, A., Caraveo, P., Cardillo, M., Cattaneo, P. W., Chen, A. W., Costa, E., Del Monte, E., Di Cocco, G., Di Persio, G., Donnarumma, I., Evangelista, Y., Feroci, M., Ferrari, A., Fioretti, V., Fuschino, F., Galli, M., Gianotti, F., Giuliani, A., Labanti, C., Lazzarotto, F., Lipari, P., Longo, F., Lucarelli, F., Magro, A., Marisaldi, M., Mereghetti, S., Morelli, E., Morselli, A., Naldi, G., Pacciani, L., Parmiggiani, N., Paoletti, F., Pellizzoni, A., Perri, M., Perotti, F., Piano, G., Picozza, P., Pilia, M., Pittori, C., Puccetti, S., Pupillo, G., Rapisarda, M., Rappoldi, A., Rubini, A., Setti, G., Soffitta, P., Trifoglio, M., Trois, A., Vercellone, S., Vittorini, V., Giommi, P., and D’Amico, F.

Published
2021
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10. Multiwavelength observations of Mrk 501 in 2008

Author

MAGIC Collaboration, Aleksić, J., Ansoldi, S., Antonelli, L. A., Antoranz, P., Babic, A., Bangale, P., de Almeida, U. Barres, Barrio, J. A., González, J. Becerra, Bednarek, W., Berger, K., Bernardini, E., Biland, A., Blanch, O., Bock, R. K., Bonnefoy, S., Bonnoli, G., Borracci, F., Bretz, T., Carmona, E., Carosi, A., Fidalgo, D. Carreto, Colin, P., Colombo, E., Contreras, J. L., Cortina, J., Covino, S., Da Vela, P., Dazzi, F., De Angelis, A., De Caneva, G., De Lotto, B., Mendez, C. Delgado, Doert, M., Domínguez, A., Prester, D. Dominis, Dorner, D., Doro, M., Einecke, S., Eisenacher, D., Elsaesser, D., Farina, E., Ferenc, D., Fonseca, M. V., Font, L., Frantzen, K., Fruck, C., López, R. J. García, Garczarczyk, M., Terrats, D. Garrido, Gaug, M., Giavitto, G., Godinović, N., Muñoz, A. González, Gozzini, S. R., Hadamek, A., Hadasch, D., Herrero, A., Hildebrand, D., Hose, J., Hrupec, D., Idec, W., Kadenius, V., Kellermann, H., Knoetig, M. L., Krause, J., Kushida, J., La Barbera, A., Lelas, D., Lewandowska, N., Lindfors, E., Lombardi, S., López, M., López-Coto, R., López-Oramas, A., Lorenz, E., Lozano, I., Makariev, M., Mallot, K., Maneva, G., Mankuzhiyil, N., Mannheim, K., Maraschi, L., Marcote, B., Mariotti, M., Martínez, M., Mazin, D., Menzel, U., Meucci, M., Miranda, J. M., Mirzoyan, R., Moralejo, A., Munar-Adrover, P., Nakajima, D., Niedzwiecki, A., Nilsson, K., Nowak, N., Orito, R., Overkemping, A., Paiano, S., Palatiello, M., Paneque, D., Paoletti, R., Paredes, J. M., Paredes-Fortuny, X., Partini, S., Persic, M., Prada, F., Moroni, P. G. Prada, Prandini, E., Preziuso, S., Puljak, I., Reinthal, R., Rhode, W., Ribó, M., Rico, J., Garcia, J. Rodriguez, Rügamer, S., Saggion, A., Saito, T., Saito, K., Salvati, M., Satalecka, K., Scalzotto, V., Scapin, V., Schultz, C., Schweizer, T., Shore, S. N., Sillanpää, A., Sitarek, J., Snidaric, I., Sobczynska, D., Spanier, F., Stamatescu, V., Stamerra, A., Steinbring, T., Storz, J., Sun, S., Surić, T., Takalo, L., Tavecchio, F., Temnikov, P., Terzić, T., Tescaro, D., Teshima, M., Thaele, J., Tibolla, O., Torres, D. F., Toyama, T., Treves, A., Uellenbeck, M., Vogler, P., Wagner, R. M., Zandanel, F., Zanin, R., Collaboration, VERITAS, Behera, B., Beilicke, M., Benbow, W., Bird, R., Bouvier, A., Bugaev, V., Cerruti, M., Chen, X., Ciupik, L., Collins-Hughes, E., Cui, W., Duke, C., Dumm, J., Falcone, A., Federici, S., Feng, Q., Finley, J. P., Fortson, L., Furniss, A., Galante, N., Gillanders, G. H., Griffin, S., Griffiths, S. T., Grube, J., Gyuk, G., Hanna, D., Holder, J., Johnson, C. A., Kaaret, P., Kertzman, M., Kieda, D., Krawczynski, H., Lang, M. J., Madhavan, A. S, Maier, G., Majumdar, P., Meagher, K., Moriarty, P., Mukherjee, R., Nieto, D., de Bhróithe, A. O'Faoláin, Ong, R. A., Otte, A. N., Pichel, A., Pohl, M., Popkow, A., Prokoph, H., Quinn, J., Rajotte, J., Ratliff, G., Reyes, L. C., Reynolds, P. T., Richards, G. T., Roache, E., Sembroski, G. H., Shahinyan, K., Sheidaei, F., Smith, A. W., Staszak, D., Telezhinsky, I., Theiling, M., Tyler, J., Varlotta, A., Vincent, S., Wakely, S. P., Weekes, T. C., Welsing, R., Williams, D. A., Zajczyk, A., Zitzer, B., Collaborators, External, Villata, M., Raiteri, C. M., Ajello, M., Perri, M., Aller, H. D., Aller, M. F., Larionov, V. M., Efimova, N. V., Konstantinova, T. S., Kopatskaya, E. N., Chen, W. P., Koptelova, E., Hsiao, H. Y., Kurtanidze, O. M., Nikolashvili, M. G., Kimeridze, G. N., Jordan, B., Leto, P., Buemi, C. S., Trigilio, C., Umana, G., Lahtenmaki, A., Nieppola, E., Tornikoski, M., Sainio, J., Giroletti, M., Cesarini, A., Fuhrmann, L., Kovalev, Yu. A., and Kovalev, Y. Y.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

Mrk 501 is one of the brightest blazars at TeV energies and has been extensively studied since its first VHE detection in 1996. Our goal is to characterize in detail the source gamma-ray emission, together with the radio-to-X-ray emission, during the non-flaring (low) activity, which is less often studied than the occasional flaring (high) activity. We organized a multiwavelength (MW) campaign on Mrk 501 between March and May 2008. This multi-instrument effort included the most sensitive VHE gamma-ray instruments in the northern hemisphere, namely the imaging atmospheric Cherenkov telescopes MAGIC and VERITAS, as well as Swift, RXTE, the F-GAMMA, GASP-WEBT, and other collaborations and instruments. Mrk 501 was found to be in a low state of activity during the campaign, with a VHE flux in the range of 10%-20% of the Crab nebula flux. Nevertheless, significant flux variations were detected with various instruments, with a trend of increasing variability with energy. The broadband spectral energy distribution during the two different emission states of the campaign can be adequately described within the homogeneous one-zone synchrotron self-Compton model, with the (slightly) higher state described by an increase in the electron number density. This agrees with previous studies of the broadband emission of this source during flaring and non-flaring states. We report for the first time a tentative X-ray-to-VHE correlation during a low VHE activity. Although marginally significant, this positive correlation between X-ray and VHE, which has been reported many times during flaring activity, suggests that the mechanisms that dominate the X-ray/VHE emission during non-flaring-activity are not substantially different from those that are responsible for the emission during flaring activity., Comment: Accepted for publication in A&A

Published
2014
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11. First broadband characterization and redshift determination of the VHE blazar MAGIC J2001+439

Author

MAGIC Collaboration, Aleksić, J., Ansoldi, S., Antonelli, L. A., Antoranz, P., Babic, A., Bangale, P., de Almeida, U. Barres, Barrio, J. A., González, J. Becerra, Bednarek, W., Bernardini, E., Biland, A., Blanch, O., Bonnefoy, S., Bonnoli, G., Borracci, F., Bretz, T., Carmona, E., Carosi, A., Fidalgo, D. Carreto, Colin, P., Colombo, E., Contreras, J. L., Cortina, J., Covino, S., Da Vela, P., Dazzi, F., De Angelis, A., De Caneva, G., De Lotto, B., Mendez, C. Delgado, Doert, M., Domínguez, A., Prester, D. Dominis, Dorner, D., Doro, M., Einecke, S., Eisenacher, D., Elsaesser, D., Farina, E., Ferenc, D., Fonseca, M. V., Font, L., Frantzen, K., Fruck, C., López, R. J. García, Garczarczyk, M., Terrats, D. Garrido, Gaug, M., Godinović, N., Muñoz, A. González, Gozzini, S. R., Hadasch, D., Hayashida, M., Herrera, J., Herrero, A., Hildebrand, D., Hose, J., Hrupec, D., Idec, W., Kadenius, V., Kellermann, H., Kodani, K., Konno, Y., Krause, J., Kubo, H., Kushida, J., La Barbera, A., Lelas, D., Lewandowska, N., Lindfors, E., Lombardi, S., López, M., López-Coto, R., López-Oramas, A., Lorenz, E., Lozano, I., Makariev, M., Mallot, K., Maneva, G., Mankuzhiyil, N., Mannheim, K., Maraschi, L., Marcote, B., Mariotti, M., Martínez, M., Mazin, D., Menzel, U., Meucci, M., Miranda, J. M., Mirzoyan, R., Moralejo, A., Munar-Adrover, P., Nakajima, D., Niedzwiecki, A., Nilsson, K., Nishijima, K., Noda, K., Nowak, N., Orito, R., Overkemping, A., Paiano, S., Palatiello, M., Paneque, D., Paoletti, R., Paredes, J. M., Paredes-Fortuny, X., Partini, S., Persic, M., Prada, F., Moroni, P. G. Prada, Prandini, E., Preziuso, S., Puljak, I., Reinthal, R., Rhode, W., Ribó, M., Rico, J., Garcia, J. Rodriguez, Rügamer, S., Saggion, A., Saito, T., Saito, K., Satalecka, K., Scalzotto, V., Scapin, V., Schultz, C., Schweizer, T., Shore, S. N., Sillanpää, A., Sitarek, J., Snidaric, I., Sobczynska, D., Spanier, F., Stamatescu, V., Stamerra, A., Steinbring, T., Storz, J., Strzys, M., Sun, S., Surić, T., Takalo, L., Takami, H., Tavecchio, F., Temnikov, P., Terzić, T., Tescaro, D., Teshima, M., Thaele, J., Tibolla, O., Torres, D. F., Toyama, T., Treves, A., Uellenbeck, M., Vogler, P., Wagner, R. M., Zandanel, F., Zanin, R., D'Ammando, F., Hovatta, T., Larionov, V. M., Max-Moerbeck, W., Perri, M., Readhead, A. C. S., Richards, J. L., Sakamoto, T., Schwartz, R. D., Verrecchia, F., and Reyes, L. C.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

We aim to characterize the broadband emission from 2FGL J2001.1+4352, which has been associated with the unknown-redshift blazar MG4 J200112+4352. Based on its gamma-ray spectral properties, it was identified as a potential very high energy (VHE; E > 100 GeV) gamma-ray emitter. The source was observed with MAGIC first in 2009 and later in 2010 within a multi-instrument observation campaign. The MAGIC observations yielded 14.8 hours of good quality stereoscopic data. The object was monitored at radio, optical and gamma-ray energies during the years 2010 and 2011. The source, named MAGIC J2001+439, is detected for the first time at VHE with MAGIC at a statistical significance of 6.3 {\sigma} (E > 70 GeV) during a 1.3-hour long observation on 2010 July 16. The multi-instrument observations show variability in all energy bands with the highest amplitude of variability in the X-ray and VHE bands. We also organized deep imaging optical observations with the Nordic Optical Telescope in 2013 to determine the source redshift. We determine for the first time the redshift of this BL Lac object through the measurement of its host galaxy during low blazar activity. Using the observational evidence that the luminosities of BL Lac host galaxies are confined to a relatively narrow range, we obtain z = 0.18 +/- 0.04. Additionally, we use the Fermi-LAT and MAGIC gamma-ray spectra to provide an independent redshift estimation, z = 0.17 +/- 0.10. Using the former (more accurate) redshift value, we adequately describe the broadband emission with a one-zone SSC model for different activity states and interpret the few-day timescale variability as produced by changes in the high-energy component of the electron energy distribution., Comment: 17 pages, 15 figures, Accepted for publication in A&A

Published
2014
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12. GRB 130427A: a Nearby Ordinary Monster

Author

Maselli, A., Melandri, A., Nava, L., Mundell, C. G., Kawai, N., Campana, S., Covino, S., Cummings, J. R., Cusumano, G., Evans, P. A., Ghirlanda, G., Ghisellini, G., Guidorzi, C., Kobayashi, S., Kuin, P., La Parola, V., Mangano, V., Oates, S., Sakamoto, T., Serino, M., Virgili, F., Zhang, B. -B., Barthelmy, S., Beardmore, A., Bernardini, M. G., Bersier, D., Burrows, D., Calderone, G., Capalbi, M., Chiang, J., D'Avanzo, P., D'Elia, V., De Pasquale, M., Fugazza, D., Gehrels, N., Gomboc, A., Harrison, R., Hanayama, H., Japelj, J., Kennea, J., Kopac, D., Kouveliotou, C., Kuroda, D., Levan, A., Malesani, D., Marshall, F., Nousek, J., O'Brien, P., Osborne, J. P., Pagani, C., Page, K. L., Page, M., Perri, M., Pritchard, T., Romano, P., Saito, Y., Sbarufatti, B., Salvaterra, R., Steele, I., Tanvir, N., Vianello, G., Wiegand, B., Wiersema, K., Yatsu, Y., Yoshii, T., and Tagliaferri, G.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

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 luminosity ($L\sim 3 \times 10^{53}$ erg s$^{-1}$) and its relative proximity ($z=0.34$), GRB 130427A was a unique event that reached the highest fluence observed in the gamma-ray band. Here we present a comprehensive multiwavelength view of GRB 130427A with Swift, the 2-m Liverpool and Faulkes telescopes and by other ground-based facilities, highlighting the evolution of the burst emission from the prompt to the afterglow phase. The properties of GRB 130427A are similar to those of the most luminous, high-redshift GRBs, suggesting that a common central engine is responsible for producing GRBs in both the contemporary and the early Universe and over the full range of GRB isotropic energies., Comment: 64 pages, 11 figures; published in Science. Update for a few references and correction of a typo in the name of one of the authors

Published
2013
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13. Monte Carlo studies for the optimisation of the Cherenkov Telescope Array layout

Author

Acharyya, A., Agudo, I., Angüner, E.O., Alfaro, R., Alfaro, J., Alispach, C., Aloisio, R., Alves Batista, R., Amans, J.-P., Amati, L., Amato, E., Ambrosi, G., Antonelli, L.A., Aramo, C., Armstrong, T., Arqueros, F., Arrabito, L., Asano, K., Ashkar, H., Balazs, C., Balbo, M., Balmaverde, B., Barai, P., Barbano, A., Barkov, M., Barres de Almeida, U., Barrio, J.A., Bastieri, D., Becerra González, J., Becker Tjus, J., Bellizzi, L., Benbow, W., Bernardini, E., Bernardos, M.I., Bernlöhr, K., Berti, A., Berton, M., Bertucci, B., Beshley, V., Biasuzzi, B., Bigongiari, C., Bird, R., Bissaldi, E., Biteau, J., Blanch, O., Blazek, J., Boisson, C., Bonanno, G., Bonardi, A., Bonavolontá, C., Bonnoli, G., Bordas, P., Böttcher, M., Bregeon, J., Brill, A., Brown, A.M., Brügge, K., Brun, P., Bruno, P., Bulgarelli, A., Bulik, T., Burton, M., Burtovoi, A., Busetto, G., Cameron, R., Canestrari, R., Capalbi, M., Caproni, A., Capuzzo-Dolcetta, R., Caraveo, P., Caroff, S., Carosi, R., Casanova, S., Cascone, E., Cassol, F., Catalani, F., Catalano, O., Cauz, D., Cerruti, M., Chaty, S., Chen, A., Chernyakova, M., Chiaro, G., Cieślar, M., Colak, S.M., Conforti, V., Congiu, E., Contreras, J.L., Cortina, J., Costa, A., Costantini, H., Cotter, G., Cristofari, P., Cumani, P., Cusumano, G., D’Aí, A., D’Ammando, F., Dangeon, L., Da Vela, P., Dazzi, F., De Angelis, A., De Caprio, V., de Cássia dos Anjos, R., De Frondat, F., de Gouveia Dal Pino, E.M., De Lotto, B., De Martino, D., de Naurois, M., de Oña Wilhelmi, E., de Palma, F., de Souza, V., Del Santo, M., Delgado, C., della Volpe, D., Di Girolamo, T., Di Pierro, F., Di Venere, L., Díaz, C., Diebold, S., Djannati-Ataï, A., Dmytriiev, A., Dominis Prester, D., Donini, A., Dorner, D., Doro, M., Dournaux, J.-L., Ebr, J., Ekoume, T.R.N., Elsässer, D., Emery, G., Falceta-Goncalves, D., Fedorova, E., Fegan, S., Feng, Q., Ferrand, G., Fiandrini, E., Fiasson, A., Filipovic, M., Fioretti, V., Fiori, M., Flis, S., Fonseca, M.V., Fontaine, G., Freixas Coromina, L., Fukami, S., Fukui, Y., Funk, S., Füßling, M., Gaggero, D., Galanti, G., Garcia López, R.J., Garczarczyk, M., Gascon, D., Gasparetto, T., Gaug, M., Ghalumyan, A., Gianotti, F., Giavitto, G., Giglietto, N., Giordano, F., Giroletti, M., Gironnet, J., Glicenstein, J.-F., Gnatyk, R., Goldoni, P., González, J.M., González, M.M., Gourgouliatos, K.N., Grabarczyk, T., Granot, J., Green, D., Greenshaw, T., Grondin, M.-H., Gueta, O., Hadasch, D., Hassan, T., Hayashida, M., Heller, M., Hervet, O., Hinton, J., Hiroshima, N., Hnatyk, B., Hofmann, W., Horvath, P., Hrabovsky, M., Hrupec, D., Humensky, T.B., Hütten, M., Inada, T., Iocco, F., Ionica, M., Iori, M., Iwamura, Y., Jamrozy, M., Janecek, P., Jankowsky, D., Jean, P., Jouvin, L., Jurysek, J., Kaaret, P., Kadowaki, L.H.S., Karkar, S., Kerszberg, D., Khélifi, B., Kieda, D., Kimeswenger, S., Kluźniak, W., Knapp, J., Knödlseder, J., Kobayashi, Y., Koch, B., Kocot, J., Komin, N., Kong, A., Kowal, G., Krause, M., Kubo, H., Kushida, J., Kushwaha, P., La Parola, V., La Rosa, G., Lallena Arquillo, M., Lang, R.G., Lapington, J., Le Blanc, O., Lefaucheur, J., Leigui de Oliveira, M.A., Lemoine-Goumard, M., Lenain, J.-P., Leto, G., Lico, R., Lindfors, E., Lohse, T., Lombardi, S., Longo, F., Lopez, A., López, M., Lopez-Oramas, A., López-Coto, R., Loporchio, S., Luque-Escamilla, P.L., Lyard, E., Maccarone, M.C., Mach, E., Maggio, C., Majumdar, P., Malaguti, G., Mallamaci, M., Mandat, D., Maneva, G., Manganaro, M., Mangano, S., Marculewicz, M., Mariotti, M., Martí, J., Martínez, M., Martínez, G., Martínez-Huerta, H., Masuda, S., Maxted, N., Mazin, D., Meunier, J.-L., Meyer, M., Micanovic, S., Millul, R., Minaya, I.A., Mitchell, A., Mizuno, T., Moderski, R., Mohrmann, L., Montaruli, T., Moralejo, A., Morcuende, D., Morlino, G., Morselli, A., Moulin, E., Mukherjee, R., Munar, P., Mundell, C., Murach, T., Nagai, A., Nagayoshi, T., Naito, T., Nakamori, T., Nemmen, R., Niemiec, J., Nieto, D., Nievas Rosillo, M., Nikołajuk, M., Ninci, D., Nishijima, K., Noda, K., Nosek, D., Nöthe, M., Nozaki, S., Ohishi, M., Ohtani, Y., Okumura, A., Ong, R.A., Orienti, M., Orito, R., Ostrowski, M., Otte, N., Ou, Z., Oya, I., Pagliaro, A., Palatiello, M., Palatka, M., Paoletti, R., Paredes, J.M., Pareschi, G., Parmiggiani, N., Parsons, R.D., Patricelli, B., Pe’er, A., Pech, M., Peñil Del Campo, P., Pérez-Romero, J., Perri, M., Persic, M., Petrucci, P.-O., Petruk, O., Pfrang, K., Piel, Q., Pietropaolo, E., Pohl, M., Polo, M., Poutanen, J., Prandini, E., Produit, N., Prokoph, H., Prouza, M., Przybilski, H., Pühlhofer, G., Punch, M., Queiroz, F., Quirrenbach, A., Rainò, S., Rando, R., Razzaque, S., Reimer, O., Renault-Tinacci, N., Renier, Y., Ribeiro, D., Ribó, M., Rico, J., Rieger, F., Rizi, V., Rodriguez Fernandez, G., Rodriguez-Ramirez, J.C., Rodrí-guez Vázquez, J.J., Romano, P., Romeo, G., Roncadelli, M., Rosado, J., Rowell, G., Rudak, B., Rugliancich, A., Rulten, C., Sadeh, I., Saha, L., Saito, T., Sakurai, S., Salesa Greus, F., Sangiorgi, P., Sano, H., Santander, M., Santangelo, A., Santos-Lima, R., Sanuy, A., Satalecka, K., Saturni, F.G., Sawangwit, U., Schlenstedt, S., Schovanek, P., Schussler, F., Schwanke, U., Sciacca, E., Scuderi, S., Sedlaczek, K., Seglar-Arroyo, M., Sergijenko, O., Seweryn, K., Shalchi, A., Shellard, R.C., Siejkowski, H., Sillanpää, A., Sinha, A., Sironi, G., Sliusar, V., Slowikowska, A., Sol, H., Specovius, A., Spencer, S., Spengler, G., Stamerra, A., Stanič, S., Stawarz, Ł., Stefanik, S., Stolarczyk, T., Straumann, U., Suomijarvi, T., Świerk, P., Szepieniec, T., Tagliaferri, G., Tajima, H., Tam, T., Tavecchio, F., Taylor, L., Tejedor, L.A., Temnikov, P., Terzic, T., Testa, V., Tibaldo, L., Todero Peixoto, C.J., Tokanai, F., Tomankova, L., Tonev, D., Torres, D.F., Tosti, G., Tosti, L., Tothill, N., Toussenel, F., Tovmassian, G., Travnicek, P., Trichard, C., Umana, G., Vagelli, V., Valentino, M., Vallage, B., Vallania, P., Valore, L., Vandenbroucke, J., Varner, G.S., Vasileiadis, G., Vassiliev, V., Vázquez Acosta, M., Vecchi, M., Vercellone, S., Vergani, S., Vettolani, G.P., Viana, A., Vigorito, C.F., Vink, J., Vitale, V., Voelk, H., Vollhardt, A., Vorobiov, S., Wagner, S.J., Walter, R., Werner, F., White, R., Wierzcholska, A., Will, M., Williams, D.A., Wischnewski, R., Yang, L., Yoshida, T., Yoshikoshi, T., Zacharias, M., Zampieri, L., Zavrtanik, M., Zavrtanik, D., Zdziarski, A.A., Zech, A., Zechlin, H., Zenin, A., Zhdanov, V.I., Zimmer, S., and Zorn, J.

Published
2019
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14. Bright X-ray Flares in Gamma-Ray Burst Afterglows

Author

Burrows, D. N., Romano, P., Falcone, A., Kobayashi, S., Zhang, B., Moretti, A., O'Brien, P. T., Goad, M. R., Campana, S., Page, K. L., Angelini, L., Barthelmy, S., Beardmore, A. P., Capalbi, M., Chincarini, G., Cummings, J., Cusumano, G., Fox, D., Giommi, P., Hill, J. E., Kennea, J. A., Krimm, H., Mangano, V., Marshall, F., Meszaros, P., Morris, D. C., Nousek, J. A., Osborne, J. P., Pagani, C., Perri, M., Tagliaferri, G., Wells, A. A., Woosley, S., and Gehrels, N.

Subjects
Astrophysics
Abstract

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 information on the central engine that powers the burst. We report the discovery of two bright X-ray flares in GRB afterglows, including a giant flare comparable in total energy to the burst itself, each peaking minutes after the burst. These strong, rapid X-ray flares imply that the central engines of the bursts have long periods of activity, with strong internal shocks continuing for hundreds of seconds after the gamma-ray emission has ended., Comment: 12 pages, 1 table, 2 figures. Originally submitted to Nature on 6/6/05. Declined on 6/9/05. Revised and submitted to Science on 6/14/05. Accepted for publication in Science on 7/29/05 (this version)

Published
2005
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15. Observation of inverse Compton emission from a long γ-ray burst

Author

Veres, P., Bhat, P. N., Briggs, M. S., Cleveland, W. H., Hamburg, R., Hui, C. M., Mailyan, B., Preece, R. D., Roberts, O. J., von Kienlin, A., Wilson-Hodge, C. A., Kocevski, D., Arimoto, M., Tak, D., Asano, K., Axelsson, M., Barbiellini, G., Bissaldi, E., Dirirsa, F. Fana, Gill, R., Granot, J., McEnery, J., Omodei, N., Razzaque, S., Piron, F., Racusin, J. L., Thompson, D. J., Campana, S., Bernardini, M. G., Kuin, N. P. M., Siegel, M. H., Cenko, S. B., O’Brien, P., Capalbi, M., Daì, A., De Pasquale, M., Gropp, J., Klingler, N., Osborne, J. P., Perri, M., Starling, R. L. C., Tagliaferri, G., Tohuvavohu, A., Ursi, A., Tavani, M., Cardillo, M., Casentini, C., Piano, G., Evangelista, Y., Verrecchia, F., Pittori, C., Lucarelli, F., Bulgarelli, A., Parmiggiani, N., Anderson, G. E., Anderson, J. P., Bernardi, G., Bolmer, J., Caballero-García, M. D., Carrasco, I. M., Castellón, A., Segura, N. Castro, Castro-Tirado, A. J., Cherukuri, S. V., Cockeram, A. M., D’Avanzo, P., Di Dato, A., Diretse, R., Fender, R. P., Fernández-García, E., Fynbo, J. P. U., Fruchter, A. S., Greiner, J., Gromadzki, M., Heintz, K. E., Heywood, I., van der Horst, A. J., Hu, Y.-D., Inserra, C., Izzo, L., Jaiswal, V., Jakobsson, P., Japelj, J., Kankare, E., Kann, D. A., Kouveliotou, C., Klose, S., Levan, A. J., Li, X. Y., Lotti, S., Maguire, K., Malesani, D. B., Manulis, I., Marongiu, M., Martin, S., Melandri, A., Michałowski, M. J., Miller-Jones, J. C. A., Misra, K., Moin, A., Mooley, K. P., Nasri, S., Nicholl, M., Noschese, A., Novara, G., Pandey, S. B., Peretti, E., del Pulgar, C. J. Pérez, Pérez-Torres, M. A., Perley, D. A., Piro, L., Ragosta, F., Resmi, L., Ricci, R., Rossi, A., Sánchez-Ramírez, R., Selsing, J., Schulze, S., Smartt, S. J., Smith, I. A., Sokolov, V. V., Stevens, J., Tanvir, N. R., Thöne, C. C., Tiengo, A., Tremou, E., Troja, E., de Ugarte Postigo, A., Valeev, A. F., Vergani, S. D., Wieringa, M., Woudt, P. A., Xu, D., Yaron, O., and Young, D. R.

Published
2019
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17. Theophylline action on primary human bronchial epithelial cells under proinflammatory stimuli and steroidal drugs: a therapeutic rationale approach

Author

Gallelli L, Falcone D, Cannataro R, Perri M, Serra R, Pelaia G, Maselli R, Savino R, Spaziano G, and D’Agostino B

Subjects
human bronchial epithelial cells, theophylline, corticosteroids, signal transduction., Therapeutics. Pharmacology, RM1-950
Abstract

Luca Gallelli,1,* Daniela Falcone,1,* Roberto Cannataro,2 Mariarita Perri,2 Raffaele Serra,3 Girolamo Pelaia,3 Rosario Maselli,3 Rocco Savino,1 Giuseppe Spaziano,4 Bruno D’Agostino4 1Department of Health Science, University of Catanzaro, Catanzaro, 2Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Rende, 3Department of Medical and Surgical Sciences, University of Catanzaro, Catanzaro, 4Department of Experimental Medicine, School of Medicine, Section of Pharmacology, Second University of Naples, Naples, Italy *These authors contributed equally to this work Abstract: Theophylline is a natural compound present in tea. Because of its property to relax smooth muscle it is used in pharmacology for the treatment of airway diseases (ie, chronic obstructive pulmonary disease, asthma). However, this effect on smooth muscle is dose dependent and it is related to the development of side effects. Recently, an increasing body of evidence suggests that theophylline, at low concentrations, also has anti-inflammatory effects related to the activation of histone deacetylases. In this study, we evaluated the effects of theophylline alone and in combination with corticosteroids on human bronchial epithelial cells under inflammatory stimuli. Theophylline administrated alone was not able to reduce growth-stimulating signaling via extracellular signal-regulated kinases activation and matrix metalloproteases release, whereas it strongly counteracts this biochemical behavior when administered in the presence of corticosteroids. These data provide scientific evidence for supporting the rationale for the pharmacological use of theophylline and corticosteroid combined drug. Keywords: human bronchial epithelial cells, theophylline, corticosteroids, signal transduction

Published
2017

18. 44 Ti gamma-ray emission lines from SN1987A reveal an asymmetric explosion

Author

Boggs, S. E., Harrison, F. A., Miyasaka, H., Grefenstette, B. W., Zoglauer, A., Fryer, C. L., Reynolds, S. P., Alexander, D. M., An, H., Barret, D., Christensen, F. E., Craig, W. W., Forster, K., Giommi, P., Hailey, C. J., Hornstrup, A., Kitaguchi, T., Koglin, J. E., Madsen, K. K., Mao, P. H., Mori, K., Perri, M., Pivovaroff, M. J., Puccetti, S., Rana, V., Stern, D., Westergaard, N. J., and Zhang, W. W.

Published
2015

19. Tracking the spectral properties of ESO 511-G030 across different epochs

Author

Middei, R, Petrucci, P, Bianchi, S, Ursini, F, Matzeu, Ga, Vagnetti, F, Tortosa, A, Marinucci, A, Matt, G, Piconcelli, E, De Rosa, A, De Marco, B, Reeves, J, Perri, M, Guainazzi, M, Cappi, M, Done, C, Middei, R., Petrucci, P. -O., and Bianchi, S.

Subjects
Settore FIS/05, Space and Planetary Science, astro-ph.GA, Astronomy and Astrophysics
Abstract

The Type 1 active galactic nucleus (AGN) ESO 511-G030, a formerly bright and soft excess dominated source, was observed in 2019 in the context of a multi-wavelength monitoring campaign. In the new exposures, the source was found to be in a flux state approximately ten times lower than archival exposures and without any trace of the soft excess. Interestingly, the X-ray weakening observed in the 2019 data corresponds to a comparable fading of the UV flux, suggesting a strong link between these two components. The UV-X-ray spectral energy distribution (SED) of ESO 511-G030 shows remarkable variability. We tested both phenomenological and physically motivated models on the data, finding that the overall emission spectrum of ESO 511-G030 in this extremely low flux state is due to the superposition of a power-law-like continuum (Γ ∼ 1.7) and two reflection components emerging from hot and cold matter. Both the primary X-ray continuum and relativistic reflection are produced in the inner regions close to the supermassive black hole. The prominent variability of ESO 511-G030 and the lack of a soft excess can be explained by the dramatic change in the observed accretion rate, which dropped from an L/LEdd of 2% in 2007 to one of 0.2% in 2019. The X-ray photon index also became harder during the low flux observations from 2019, perhaps as a result of a photon starved X-ray corona.

Published
2023
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21. Web-Based Job Submission Interface for the GAMESS Computational Chemistry Program

Author

Perri, M. J. and Weber, S. H.

Abstract

A Web site is described that facilitates use of the free computational chemistry software: General Atomic and Molecular Electronic Structure System (GAMESS). Its goal is to provide an opportunity for undergraduate students to perform computational chemistry experiments without the need to purchase expensive software.

Published
2014
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22. X-Ray Flares in Early GRB Afterglows

Author

Burrows, D. N., Falcone, A., Chincarini, G., Morris, D., Romano, P., Hill, J. E., Godet, O., Moretti, A., Krimm, H., Osborne, J. P., Racusin, J., Mangano, V., Page, K., Perri, M., and Stroh, M.

Published
2007
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23. Extremes of the Jet-Accretion Power Relation of Blazars, as Explored by Nustar

Author

Sbarrato, T, Ghisellini, G, Tagliaferri, G, Perri, M, Madejski, G. M, Stern, D, Boggs, S. E, Christensen, F. E, Craig, W. W, and Zhang, W. W

Subjects
Astrophysics
Abstract

Hard X-ray observations are crucial to study the non-thermal jet emission from high-redshift, powerful blazars. We observed two bright z > 2 flat-spectrum radio quasars (FSRQs) in hard X-rays to explore the details of their relativistic jets and their possible variability. S50014+81 (at z = 3.366) and B0222+185 (at z = 2.690) have been observed twice by the Nuclear Spectroscopic Telescope Array (NuSTAR) simultaneously with Swift X-ray Telescope, showing different variability behaviors. We found that NuSTAR is instrumental to explore the variability of powerful high-redshift blazars, even when no gamma-ray emission is detected. The two sources have proven to have respectively the most luminous accretion disc and the most powerful jet among known blazars. Thanks to these properties, they are located at the extreme end of the jet-accretion disc relation previously found for gamma-ray detected blazars, to which they are consistent.

Published
2016
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24. SUPERNOVAE: 44Ti gamma-ray emission lines from SN1987A reveal an asymmetric explosion

Author

Boggs, S. E., Harrison, F. A., Miyasaka, H., Grefenstette, B. W., Zoglauer, A., Fryer, C. L., Reynolds, S. P., Alexander, D. M., An, H., Barret, D., Christensen, F. E., Craig, W. W., Forster, K., Giommi, P., Hailey, C. J., Hornstrup, A., Kitaguchi, T., Koglin, J. E., Madsen, K. K., Mao, P. H., Mori, K., Perri, M., Pivovaroff, M. J., Puccetti, S., Rana, V., Stern, D., Westergaard, N. J., and Zhang, W. W.

Published
2015
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31. Asymmetries in core-collapse supernovae from maps of radioactive 44Ti in Cassiopeia A

Author

Grefenstette, B. W., Harrison, F. A., Boggs, S. E., Reynolds, S. P., Fryer, C. L., Madsen, K. K., Wik, D. R., Zoglauer, A., Ellinger, C. I., Alexander, D. M., An, H., Barret, D., Christensen, F. E., Craig, W. W., Forster, K., Giommi, P., Hailey, C. J., Hornstrup, A., Kaspi, V. M., Kitaguchi, T., Koglin, J. E., Mao, P. H., Miyasaka, H., Mori, K., Perri, M., Pivovaroff, M. J., Puccetti, S., Rana, V., Stern, D., Westergaard, N. J., and Zhang, W. W.

Published
2014
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33. GRB 130427A: A Nearby Ordinary Monster

Author

Maselli, A., Melandri, A., Nava, L., Mundell, C. G., Kawai, N., Campana, S., Covino, S., Cummings, J. R., Cusumano, G., Evans, P. A., Ghirlanda, G., Ghisellini, G., Guidorzi, C., Kobayashi, S., Kuin, P., La Parola, V., Mangano, V., Oates, S., Sakamoto, T., Serino, M., Virgili, F., Zhang, B.-B., Barthelmy, S., Beardmore, A., Bernardini, M. G., Bersier, D., Burrows, D., Calderone, G., Capalbi, M., Chiang, J., DʼAvanzo, P., DʼElia, V., De Pasquale, M., Fugazza, D., Gehrels, N., Gomboc, A., Harrison, R., Hanayama, H., Japelj, J., Kennea, J., Kopac, D., Kouveliotou, C., Kuroda, D., Levan, A., Malesani, D., Marshall, F., Nousek, J., OʼBrien, P., Osborne, J. P., Pagani, C., Page, K. L., Page, M., Perri, M., Pritchard, T., Romano, P., Saito, Y., Sbarufatti, B., Salvaterra, R., Steele, I., Tanvir, N., Vianello, G., Weigand, B., Wiersema, K., Yatsu, Y., Yoshii, T., and Tagliaferri, G.

Published
2014

36. first hard X-ray spectral catalogue of Blazars observed by NuSTAR.

Author

Middei, R, Giommi, P, Perri, M, Turriziani, S, Sahakyan, N, Chang, Y L, Leto, C, and Verrecchia, F

Subjects
HARD X-rays, SPECTRAL energy distribution, SOLAR flares, ACTIVE galactic nuclei, BL Lacertae objects, DOWNLOADING
Abstract

Blazars are a peculiar class of active galactic nuclei that enlighten the sky at all wavelengths. The electromagnetic emission of these sources is jet-dominated, resulting in a spectral energy distribution (SED) that has a typical double-humped shape. X-ray photons provide a wealth of information on the physics of each source as in the X-ray band, we can observe the tail of SED first peak, the rise of the second one or the transition between the two. NuSTAR , thanks to its capability of focusing X-rays up to 79 keV provides broad-band data particularly suitable to compute SEDs in a still poorly explored part of the spectrum. In the context of the Open Universe initiative, we developed a dedicated pipeline, NuSTAR_Spectra , a shell-script that automatically downloads data from the archive, generates scientific products and carries out a complete spectral analysis. The script homogeneously extracts high level scientific products for both NuSTAR 's telescopes and the spectral characterization is performed testing two phenomenological models. The corresponding X-ray properties are derived from the data best fit, and the SEDs are also computed. The systematic processing of all blazar observations of the NuSTAR public archive allowed us to release the first hard X-ray spectroscopic catalogue of blazars (NuBlazar). The catalogue, updated to 2021 September 30, includes 253 observations of 126 distinct blazars, 30 of which have been multiply observed. [ABSTRACT FROM AUTHOR]

Published
2022
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37. lively accretion disc in NGC 2992 – II. The 2019/2021 X-ray monitoring campaigns.

Author

Middei, R, Marinucci, A, Braito, V, Bianchi, S, De Marco, B, Luminari, A, Matt, G, Nardini, E, Perri, M, Reeves, J N, and Vagnetti, F

Subjects
ACCRETION disks, X-rays, SEYFERT galaxies, ENERGY bands, MOLECULAR spectra
Abstract

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 targeted the source more than 100 times between 2019 and 2021 in the context of two monitoring campaigns. Both time-averaged and time-resolved analyses are performed, and we find that the short-to-long term spectral properties of NGC 2992 are dominated by a highly variable nuclear continuum. The source varied in the 2–10 keV energy band from 0.6 to 12 × 10−11 erg cm−2 s−1 during the two year long Swift monitoring. The fastest 2–10 keV flux change (by a factor of |$\sim 60{{\ \rm per\ cent}}$|⁠) occurred on a time-scale of a few hours. The overall emission spectrum of the source is consistent with a power law-like continuum (Γ = 1.69 ± 0.01) absorbed by a constant line-of-sight column density N H = (7.8 ± 0.1) × 1021 |$\rm cm^{-2}$|⁠. The reflected emission is likely due to matter with an average column density N H = (9.6 ± 2.7) × 1022 |$\rm cm^{-2}$|⁠ , thus NGC 2992 appears to have a globally Compton-thin circumnuclear medium. This scenario is fully supported by an independent analysis of the fractional variability and by XMM–Newton multiyear spectra. [ABSTRACT FROM AUTHOR]

Published
2022
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40. Relativistic jet activity from the tidal disruption of a star by a massive black hole

Author

Burrows, D. N., Kennea, J. A., Ghisellini, G., Mangano, V., Zhang, B., Page, K. L., Eracleous, M., Romano, P., Sakamoto, T., Falcone, A. D., Osborne, J. P., Campana, S., Beardmore, A. P., Breeveld, A. A., Chester, M. M., Corbet, R., Covino, S., Cummings, J. R., DʼAvanzo, P., DʼElia, V., Esposito, P., Evans, P. A., Fugazza, D., Gelbord, J. M., Hiroi, K., Holland, S. T., Huang, K. Y., Im, M., Israel, G., Jeon, Y., Jeon, Y. B., Jun, H. D., Kawai, N., Kim, J. H., Krimm, H. A., Marshall, F. E., Mészáros, P., Negoro, H., Omodei, N., Park, W. K., Perkins, J. S., Sugizaki, M., Sung, H. I., Tagliaferri, G., Troja, E., Ueda, Y., Urata, Y., Usui, R., Antonelli, L. A., Barthelmy, S. D., Cusumano, G., Giommi, P., Melandri, A., Perri, M., Racusin, J. L., Sbarufatti, B., Siegel, M. H., and Gehrels, N.

Published
2011
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42. A γ-ray burst at a redshift of z ≈ 8.2

Author

Tanvir, N. R., Fox, D. B., Levan, A. J., Berger, E., Wiersema, K., Fynbo, J. P. U., Cucchiara, A., Krühler, T., Gehrels, N., Bloom, J. S., Greiner, J., Evans, P. A., Rol, E., Olivares, F., Hjorth, J., Jakobsson, P., Farihi, J., Willingale, R., Starling, R. L. C., Cenko, S. B., Perley, D., Maund, J. R., Duke, J., Wijers, R. A. M. J., Adamson, A. J., Allan, A., Bremer, M. N., Burrows, D. N., Castro-Tirado, A. J., Cavanagh, B., de Ugarte Postigo, A., Dopita, M. A., Fatkhullin, T. A., Fruchter, A. S., Foley, R. J., Gorosabel, J., Kennea, J., Kerr, T., Klose, S., Krimm, H. A., Komarova, V. N., Kulkarni, S. R., Moskvitin, A. S., Mundell, C. G., Naylor, T., Page, K., Penprase, B. E., Perri, M., Podsiadlowski, P., Roth, K., Rutledge, R. E., Sakamoto, T., Schady, P., Schmidt, B. P., Soderberg, A. M., Sollerman, J., Stephens, A. W., Stratta, G., Ukwatta, T. N., Watson, D., Westra, E., Wold, T., and Wolf, C.

Published
2009
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43. Fermi Observations of High-Energy Gamma-Ray Emission from GRB 080916C

Author

Abdo, A. A., Ackermann, M., Arimoto, M., Asano, K., Atwood, W. B., Axelsson, M., Baldini, L., Ballet, J., Band, D. L., Barbiellini, G., Baring, M. G., Bastieri, D., Battelino, M., Baughman, B. M., Bechtol, K., Bellardi, F., Bellazzini, R., Berenji, B., Bhat, P. N., Bissaldi, E., Blandford, R. D., Bloom, E. D., Bogaert, G., Bogart, J. R., Bonamente, E., Bonnell, J., Borgland, A. W., Bouvier, A., Bregeon, J., Brez, A., Briggs, M. S., Brigida, M., Bruel, P., Burnett, T. H., Burrows, D., Busetto, G., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Casandjian, J. M., Ceccanti, M., Cecchi, C., Celotti, A., Charles, E., Chekhtman, A., Cheung, C. C., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Cominsky, L. R., Connaughton, V., Conrad, J., Costamante, L., Cutini, S., DeKlotz, M., Dermer, C. D., de Angelis, A., de Palma, F., Digel, S. W., Dingus, B. L., do Couto e Silva, E., Drell, P. S., Dubois, R., Dumora, D., Edmonds, Y., Evans, P. A., Fabiani, D., Farnier, C., Favuzzi, C., Finke, J., Fishman, G., Focke, W. B., Frailis, M., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Giebels, B., Giglietto, N., Giommi, P., Giordano, F., Glanzman, T., Godfrey, G., Goldstein, A., Granot, J., Greiner, J., Grenier, I. A., Grondin, M.-H., Grove, J. E., Guillemot, L., Guiriec, S., Haller, G., Hanabata, Y., Harding, A. K., Hayashida, M., Hays, E., Morata, Hernando J. A., Hoover, A., Hughes, R. E., Jóhannesson, G., Johnson, A. S., Johnson, R. P., Johnson, T. J., Johnson, W. N., Kamae, T., Katagiri, H., Kataoka, J., Kavelaars, A., Kawai, N., Kelly, H., Kennea, J., Kerr, M., Kippen, R. M., Knödlseder, J., Kocevski, D., Kocian, M. L., Komin, N., Kouveliotou, C., Kuehn, F., Kuss, M., Lande, J., Landriu, D., Larsson, S., Latronico, L., Lavalley, C., Lee, B., Lee, S.-H., Lemoine-Goumard, M., Lichti, G. G., Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Madejski, G. M., Makeev, A., Marangelli, B., Mazziotta, M. N., McBreen, S., McEnery, J. E., McGlynn, S., Meegan, C., Mészáros, P., Meurer, C., Michelson, P. F., Minuti, M., Mirizzi, N., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Monte, C., Monzani, M. E., Moretti, E., Morselli, A., Moskalenko, I. V., Murgia, S., Nakamori, T., Nelson, D., Nolan, P. L., Norris, J. P., Nuss, E., Ohno, M., Ohsugi, T., Okumura, A., Omodei, N., Orlando, E., Ormes, J. F., Ozaki, M., Paciesas, W. S., Paneque, D., Panetta, J. H., Parent, D., Pelassa, V., Pepe, M., Perri, M., Pesce-Rollins, M., Petrosian, V., Pinchera, M., Piron, F., Porter, T. A., Preece, R., Rainò, S., Ramirez-Ruiz, E., Rando, R., Rapposelli, E., Razzano, M., Razzaque, S., Rea, N., Reimer, A., Reimer, O., Reposeur, T., Reyes, L. C., Ritz, S., Rochester, L. S., Rodriguez, A. Y., Roth, M., Ryde, F., Sadrozinski, H. F.-W., Sanchez, D., Sander, A., Parkinson, Saz P. M., Scargle, J. D., Schalk, T. L., Segal, K. N., Sgrò, C., Shimokawabe, T., Siskind, E. J., Smith, D. A., Smith, P. D., Spandre, G., Spinelli, P., Stamatikos, M., Starck, J.-L, Stecker, F. W., Steinle, H., Stephens, T. E., Strickman, M. S., Suson, D. J., Tagliaferri, G., Tajima, H., Takahashi, H., Takahashi, T., Tanaka, T., Tenze, A., Thayer, J. B., Thayer, J. G., Thompson, D. J., Tibaldo, L., Torres, D. F., Tosti, G., Tramacere, A., Turri, M., Tuvi, S., Usher, T. L., van der Horst, A. J., Vigiani, L., Vilchez, N., Vitale, V., von Kienlin, A., Waite, A. P., Williams, D. A., Wilson-Hodge, C., Winer, B. L., Wood, K. S., Wu, X. F., Yamazaki, R., Ylinen, T., and Ziegler, M.

Published
2009

44. Broadband observations of the naked-eye γ-ray burst GRB 080319B

Author

Racusin, J. L., Karpov, S. V., Sokolowski, M., Granot, J., Wu, X. F., Pal'shin, V., Covino, S., van der Horst, A. J., Oates, S. R., Schady, P., Smith, R. J., Cummings, J., Starling, R. L. C., Piotrowski, L. W., Zhang, B., Evans, P. A., Holland, S. T., Malek, K., Page, M. T., Vetere, L., Margutti, R., Guidorzi, C., Kamble, A. P., Curran, P. A., Beardmore, A., Kouveliotou, C., Mankiewicz, L., Melandri, A., O'Brien, P. T., Page, K. L., Piran, T., Tanvir, N. R., Wrochna, G., Aptekar, R. L., Barthelmy, S., Bartolini, C., Beskin, G. M., Bondar, S., Bremer, M., Campana, S., Castro-Tirado, A., Cucchiara, A., Cwiok, M., D'Avanzo, P., D'Elia, V., Valle, M. Della, Postigo, A. de Ugarte, Dominik, W., Falcone, A., Fiore, F., Fox, D. B., Frederiks, D. D., Fruchter, A. S., Fugazza, D., Garrett, M. A., Gehrels, N., Golenetskii, S., Gomboc, A., Gorosabel, J., Greco, G., Guarnieri, A., Immler, S., Jelinek, M., Kasprowicz, G., La Parola, V., Levan, A. J., Mangano, V., Mazets, E. P., Molinari, E., Moretti, A., Nawrocki, K., Oleynik, P. P., Osborne, J. P., Pagani, C., Pandey, S. B., Paragi, Z., Perri, M., Piccioni, A., Ramirez-Ruiz, E., Roming, P. W. A., Steele, I. A., Strom, R. G., Testa, V., Tosti, G., Ulanov, M. V., Wiersema, K., Wijers, R. A. M. J., Winters, J. M., Zarnecki, A. F., Zerbi, F., Mészáros, P., Chincarini, G., and Burrows, D. N.

Published
2008
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46. An unexpectedly rapid decline in the X-ray afterglow emission of long γ-ray bursts

Author

Tagliaferri, G., Goad, M., Chincarini, G., Moretti, A., Campana, S., Burrows, D. N., Perri, M., Barthelmy, S. D., Gehrels, N., Krimm, H., Sakamoto, T., Kumar, P., Mészáros, P. I., Kobayashi, S., Zhang, B., Angelini, L., Banat, P., Berdmore, A. P., Capalbi, M., Covino, S., Cusumano, G., Giommi, P., Godet, O., Hill, J. E., Kennea, J. A., Mangano, V., Morris, D. C., Nousek, J. A., O'Brien, P. T., Osborne, J. P., Pagani, C., Page, K. L., Romano, P., Stella, L., and Wells, A.

Published
2005

49. First Results from NuSTAR Observations of Mkn 421

Author

Baloković M., Ajello M., Blandford R. D., Boggs S. E., Borracci F., Chiang J., Christensen F. E., Craig W. W., Forster K., Furniss A., Fürst F., Ghisellini G., Giebels B., Giommi P., Grefenstette B. W., Hailey C. J., Harrison F. A., Hayashida M., Humensky B., Inoue Y., Koglin J. E., Krawczynski H., Madejski G. M., Madsen K. K., Meier D. L., Nelson T., Ogle P., Paneque D., Perri M., Puccetti S., Reynolds C. S., Sbarrato T., Stern D., Tagliaferri G., Urry C. M., Wehrle A. E., and Zhang W. W.

Subjects
Physics, QC1-999
Abstract

Mkn 421 is a nearby active galactic nucleus dominated at all wavelengths by a very broad nonthermal continuum thought to arise from a relativistic jet seen at a small angle to the line of sight. Its spectral energy distribution peaks in the X-ray and TeV γ-ray bands, where the energy output is dominated by cooling of high-energy electrons in the jet. In order to study the electron distribution and its evolution, we carried out a dedicated multi-wavelength campaign, including extensive observations by the recently launched highly sensitive hard X-ray telescope NuSTAR, between December 2012 and May 2013. Here we present some initial results based on NuSTAR data from January through March 2013, as well as calibration observations conducted in 2012. Although the observations cover some of the faintest hard X-ray flux states ever observed forMkn 421, the sensitivity is high enough to resolve intra-day spectral variability. We find that in this low state the dominant flux variations are smooth on timescales of hours, with typical intra-hour variations of ≲ 5%. We do not find evidence for either a cutoff in the hard X-ray spectrum, or a rise towards a high-energy component, but rather that at low flux the spectrum assumes a power law shape with a photon index of approximately 3. The spectrum is found to harden with increasing brightness.

Published
2013
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50. X-ray spectra, light curves and SEDs of blazars frequently observed by Swift.

Author

Giommi, Paolo, Perri, M, Capalbi, M, D'Elia, V, Barres de Almeida, U, Brandt, C H, Pollock, A M T, Arneodo, F, Di Giovanni, A, Chang, Y L, Civitarese, O, De Angelis, M, Leto, C, Verrecchia, F, Ricard, N, Di Pippo, S, Middei, R, Penacchioni, A V, Ruffini, R, and Sahakyan, N

Subjects
*X-ray spectra, *LIGHT curves, *BL Lacertae objects, *SPECTRAL energy distribution, *ASTROPHYSICS, *ENERGY bands, *COSMIC rays
Abstract

Blazars research is one of the hot topics of contemporary extragalactic astrophysics. That is because these sources are the most abundant type of extragalactic γ-ray sources and are suspected to play a central role in multimessenger astrophysics. We have used Swift |$\_$| xrtproc, a tool to carry out an accurate spectral and photometric analysis of the Swift-XRT data of all blazars observed by Swift at least 50 times between December 2004 and the end of 2020. We present a database of X-ray spectra, best-fit parameter values, count rates and flux estimations in several energy bands of over 31 000 X-ray observations and single snapshots of 65 blazars. The results of the X-ray analysis have been combined with other multifrequency archival data to assemble the broad-band Spectral Energy Distributions (SEDs) and the long-term light curves of all sources in the sample. Our study shows that large X-ray luminosity variability on different time-scales is present in all objects. Spectral changes are also frequently observed with a 'harder-when-brighter' or 'softer-when-brighter' behaviour depending on the SED type of the blazars. The peak energy of the synchrotron component (νpeak) in the SED of HBL blazars, estimated from the log-parabolic shape of their X-ray spectra, also exhibits very large changes in the same source, spanning a range of over two orders of magnitude in Mrk421 and Mrk501, the objects with the best data sets in our sample. [ABSTRACT FROM AUTHOR]

Published
2021
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