269 results on '"P., Santolamazza"'
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2. Publisher Correction: How does damage control strategy influence organ's suitability for donation after major trauma? A multi-institutional study
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Altomare, Michele, Bekhor, Shir Sara, Sacchi, Marco, Ambrogi, Federico, Infante, Gabriele, Chieregato, Arturo, Pozzi, Federico, De Feo, Tullia Maria, Nava, Lorenza, Masturzo, Elisabetta, Del Prete, Luca, Perali, Carolina, Manzo, Elena, Bertoli, Paolo, Virdis, Francesco, Spota, Andrea, Cioffi, Stefano Piero Bernardo, Benuzzi, Laura, Santolamazza, Giuliano, Podda, Mauro, Mingoli, Andrea, Chiara, Osvaldo, and Cimbanassi, Stefania
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- 2024
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3. How does damage control strategy influence organ’s suitability for donation after major trauma? A multi-institutional study
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Altomare, Michele, Bekhor, Shir Sara, Sacchi, Marco, Ambrogi, Federico, Infante, Gabriele, Chieregato, Arturo, Pozzi, Federico, Feo, Tullia Maria De, Nava, Lorenza, Masturzo, Elisabetta, Prete, Luca Del, Perali, Carolina, Manzo, Elena, Bertoli, Paolo, Virdis, Francesco, Spota, Andrea, Cioffi, Stefano Piero Bernardo, Benuzzi, Laura, Santolamazza, Giuliano, Podda, Mauro, Mingoli, Andrea, Chiara, Osvaldo, and Cimbanassi, Stefania
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- 2024
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4. Correction: Contrast-enhanced ultrasound (CEUS) in the follow-up of abdominal solid organ trauma: an international survey prior to the PseAn study
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Santolamazza, Giuliano, Virdis, Francesco, Abu-Zidan, Fikri, Cioffi, Stefano Piero Bernardo, Reitano, Elisa, Altomare, Michele, Bini, Roberto, Spota, Andrea, Podda, Mauro, Kumar, Jayant, Chiara, Osvaldo, and Cimbanassi, Stefania
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- 2024
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5. A matter of sex—persistent predictive value of MECKI score prognostic power in men and women with heart failure and reduced ejection fraction: a multicenter study
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Giulia Grilli, Elisabetta Salvioni, Federica Moscucci, Alice Bonomi, Gianfranco Sinagra, Michele Schaeffer, Jeness Campodonico, Massimo Mapelli, Maddalena Rossi, Cosimo Carriere, Michele Emdin, Massimo Piepoli, Stefania Paolillo, Michele Senni, Claudio Passino, Anna Apostolo, Federica Re, Caterina Santolamazza, Damiano Magrì, Carlo M. Lombardi, Ugo Corrà, Rosa Raimondo, Antonio Cittadini, Annamaria Iorio, Andrea Salzano, Rocco Lagioia, Carlo Vignati, Roberto Badagliacca, Andrea Passantino, Pasquale Perrone Filardi, Michele Correale, Enrico Perna, Davide Girola, Marco Metra, Gaia Cattadori, Marco Guazzi, Giuseppe Limongelli, Gianfranco Parati, Fabiana De Martino, Maria Vittoria Matassini, Francesco Bandera, Maurizio Bussotti, Angela Beatrice Scardovi, Susanna Sciomer, Piergiuseppe Agostoni, MECKI Score Research Group, Armando Ferraretti, Cristina Gussago, Domenico Scrutinio, Donatella Bertipaglia, Elisa Battaia, Michele Moretti, Francesca Pietrucci, Geza Halasz, Bruno Capelli, Giovanna Gallo, Emiliano Fiori, Giovanni Marchese, Giuseppe Pacileo, Fabio Valente, Rossella Vastarella, Rita Gravino, Matilda Shkoza, Nikita Baracchini, Teresa Capovilla, Andrea Di Lenarda, Alberto Maria Marra, Roberta D’Assante, Giulia Crisci, Roberto Ricci, Luca Arcari, Sergio Caravita, Elena Viganò, Stefania Farina, Beatrice Pezzuto, Pietro Palermo, Mauro Contini, Paola Gugliandolo, Irene Mattavelli, and Michele Della Rocca
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heart failure with reduced ejection fraction ,prognosis ,sex ,MECKI score ,risk ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
BackgroundA sex-based evaluation of prognosis in heart failure (HF) is lacking.Methods and resultsWe analyzed the Metabolic Exercise test data combined with Cardiac and Kidney Indexes (MECKI) score registry, which includes HF with reduced ejection fraction (HFrEF) patients. A cross-validation procedure was performed to estimate weights separately for men and women of all MECKI score parameters: left ventricular ejection fraction (LVEF), hemoglobin, kidney function assessed by Modification of Diet in Renal Disease, blood sodium level, ventilation vs. carbon dioxide production slope, and peak oxygen consumption (peakVO2). The primary outcomes were the composite of all-cause mortality, urgent heart transplant, and implant of a left ventricle assist device. The difference in predictive ability between the native and sex recalibrated MECKI (S-MECKI) was calculated using a receiver operating characteristic (ROC) curve at 2 years and a calibration plot. We retrospectively analyzed 7,900 HFrEF patients included in the MECKI score registry (mean age 61 ± 13 years, 6,456 men/1,444 women, mean LVEF 33% ± 10%, mean peakVO2 56.2% ± 17.6% of predicted) with a median follow-up of 4.05 years (range 1.72–7.47). Our results revealed an unadjusted risk of events that was doubled in men compared to women (9.7 vs. 4.1) and a significant difference in weight between the sexes of most of the parameters included in the MECKI score. S-MECKI showed improved risk classification and accuracy (area under the ROC curve: 0.7893 vs. 0.7799, p = 0.02) due to prognostication improvement in the high-risk settings in both sexes (MECKI score >10 in men and >5 in women).ConclusionsS-MECKI, i.e., the recalibrated MECKI according to sex-specific differences, constitutes a further step in the prognostic assessment of patients with severe HFrEF.
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- 2024
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6. Contrast-enhanced ultrasound (CEUS) in the follow-up of abdominal solid organ trauma: an international survey prior to the PseAn study
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Santolamazza, Giuliano, Virdis, Francesco, Abu-Zidan, Fikri, Cioffi, Stefano Piero Bernardo, Reitano, Elisa, Altomare, Michele, Bini, Roberto, Spota, Andrea, Podda, Mauro, Kumar, Jayant, Chiara, Osvaldo, and Cimbanassi, Stefania
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- 2023
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7. Integrating Industry 4.0 and 5.0 Innovations for Enhanced Energy Management Systems
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Vito Introna, Annalisa Santolamazza, and Vittorio Cesarotti
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Energy Management Systems ,Industry 4.0 ,Industry 5.0 ,ISO 50001 ,Technology - Abstract
Industry 4.0 and Industry 5.0 have introduced a lot of innovative technologies in industrial plants, transforming them into complex digital systems. On the other hand, the importance of Energy Management Systems in industrial plants is growing for both sustainability and economic reasons, but the opportunity of Industry 4.0/5.0 technologies in enhancing energy management systems is not fully understood. Thus, this paper analyzes how Industry 4.0/5.0 technologies can be applied to meet the requirements of Energy Management Systems, focusing on each aspect such as design, monitoring, control, and budget planning. It identifies additional opportunities that arise with different levels of technological implementation, suggesting organic implementation steps. The final aim is to provide a comprehensive framework for fostering a strategic and conscious implementation approach of these tools in the Energy Management Systems of industrial plants, giving clear and comprehensive suggestions.
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- 2024
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8. Artificial intelligence unveils key interactions between soil properties and climate factors on Boletus edulis and B. reticulatus mycelium in chestnut orchards of different ages
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Serena Santolamazza-Carbone, Laura Iglesias-Bernabé, Mariana Landin, Elena Benito Rueda, M. Esther Barreal, and Pedro Pablo Gallego
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abiotic parameters ,artificial intelligence ,ectomycorrhiza ,extra-radical mycelium ,hybrid chestnuts ,plant age ,Chemistry ,QD1-999 ,Engineering geology. Rock mechanics. Soil mechanics. Underground construction ,TA703-712 - Abstract
The main objective of this study was to determine the possible interaction of two important abiotic factors (soil and climate) on the mycelial concentration and frequency of the ectomycorrhizal fungi Boletus edulis and B. reticulatus, using traditional statistics and artificial neural network tools. The frequency and concentration of Boletus mycelium were determined over three months (September, October, and November), and two years (2018 and 2020), in three hybrid chestnuts (Castanea × coudercii) orchards of 40-, 10-, and 3- years-old, using real-time qPCR. Statistical analysis revealed a significant effect of the year on B. edulis mycelium concentration and of the sampling plot (different tree ages) on B. reticulatus frequency. The combination of artificial intelligence networks (ANN) with fuzzy logic, named neurofuzzy logic (NF), allowed the construction of two robust models. In the first, using year, month, and sampling plot as inputs, NF identified hidden interactions between year and month on B. edulis mycelium concentration and between sampling plot and sampling month on B. reticulatus mycelium frequency, thus improving the information obtained from the statistical analysis. In the second model, those three factors were disaggregated into 44 inputs, including 20 soil properties and 24 climatic factors, being NF able to select only 8 as critical factors to explain the variability found in both ectomycorrhizal Boletus species regarding mycelial frequency and concentration. Specifically, NF selected two chemical soil properties (cation exchange capacity and total carbon) and three physical properties (macroaggregates, total porosity, and soil moisture at field capacity), as well as their interactions with three climatic elements (cumulative difference between precipitation and potential evapotranspiration (P-PET-1-2) and water deficit (WD-1-2) in the previous two months and excess water (WE-1) in the month prior to sampling. These results provide a much deeper understanding and new insights into the ecology and the role of abiotic factors which explain the different mycelial development patterns of ectomycorrhizal fungi such as B. edulis and B. reticulatus in chestnut agroecosystems.
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- 2023
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9. Primary cerebral cystic echinococcosis in a child from Roman countryside: Source attribution and scoping review of cases from the literature.
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Adriano Casulli, Stefania Pane, Franco Randi, Paola Scaramozzino, Andrea Carvelli, Carlo Efisio Marras, Andrea Carai, Azzurra Santoro, Federica Santolamazza, Francesca Tamarozzi, and Lorenza Putignani
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Arctic medicine. Tropical medicine ,RC955-962 ,Public aspects of medicine ,RA1-1270 - Abstract
BackgroundHuman cystic echinococcosis (CE) is a zoonotic parasitic infection caused by the larval stage of the species belonging to the Echinococcus granulosus sensu lato (s.l.) complex. Parasitic cysts causing human CE are mainly localized in the liver and in the lungs. In a smaller number of cases, larvae may establish in any organ or tissue, including the central nervous system (CNS). Cerebral CE (CCE) is rare but poses serious clinical challenges.MethodsThis study presents a case of CCE in a child living in the countryside near Rome (Italy), along with a comparative molecular analysis of the isolated cyst specimens from the patient and sheep of local farms. We also systematically searched the literature to summarize the most relevant epidemiological and clinical aspects of this uncommon localization.FindingsThe comparative molecular analysis confirmed that the infection was caused by E. granulosus sensu stricto (s.s.) (G3 genotype), and most likely acquired in the family farm. The literature search identified 2,238 cases of CCE. In 80.51% of cases, brain was the only localization and single CCE cysts were present in 84.07% of cases. Mean patients' age was 20 years and 70.46% were children. Cyst rupture was reported in 12.96% and recurrence of CCE after treatment in 9.61% of cases. Permanent disability was reported in 7.86% of cases, while death occurred in 6.21%. In case series reporting all CE localization, CCE represented 1.5% of all CE cases. In the few reports that identified at molecular level the CCE cyst, E. granulosus s.s. was found in 40% and E. canadensis in 60% of cases.ConclusionsWe report a rare case of CCE and evidenced the probable local origin of infection. The proportions of CE cases with uncommon localizations and with high impact on patients' lives have been globally neglected and should be included in the computation of the global burden of CE.
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- 2023
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10. From institutional series to online inventories: what has changed in the Soprintendenza
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Rossella Santolamazza
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Archive ,Software ,Inventory ,Archive Research Tools. ,Bibliography. Library science. Information resources - Abstract
In the panorama of the institutions of the Italian Archival Administration, the Umbria Soprintendenza archivistica e bibliografica can certainly boast a primacy: its conspicuous editorial production that started in the late 1990s and composed by the series “Segni di civiltà” and “Scaffali senza polvere”, in addition to the many exhibition catalogs. To date, in SIUSA and the SAN Portal - Online Research Tools, there are over 500 inventories of Umbrian archives, more than a quarter of the national production. What path has been taken from printed volumes to downloadable pdfs and browsing archival description software?
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- 2023
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11. Cystic echinococcosis in northern Tanzania: a pilot study in Maasai livestock-keeping communities
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Francesca Tamarozzi, Tito Kibona, William A. de Glanville, Tauta Mappi, Elly Adonikamu, Anande Salewi, Kennedy Misso, Venance Maro, Adriano Casulli, Azzurra Santoro, Federica Santolamazza, Blandina T. Mmbaga, and Sarah Cleaveland
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Echinococcus granulosus sensu lato ,Cystic echinococcosis ,Maasai ,Northern Tanzania ,Prevalence ,Genotypes ,Infectious and parasitic diseases ,RC109-216 - Abstract
Abstract Background There are close similarities between the life-cycles of Echinococcus granulosus sensu lato (E. granulosus s.l.) that causes cystic echinococcosis (CE) in humans and Taenia multiceps/Coenurus cerebralis that causes cerebral coenurosis in small ruminants. Recent evidence highlights that livestock in Maasai communities of northern Tanzania are suffering from increases in the prevalence of cerebral coenurosis, leading to concerns about a possible concurrent increased risk of human CE. The aim of this study was to estimate the prevalence of human abdominal CE and the prevalence and species/genotypes of E. granulosus s.l. in livestock in Maasai communities. Methods Human CE was diagnosed by abdominal ultrasound on volunteers aged ≥ 7 years in five villages in the Longido and Ngorongoro Districts in northern Tanzania. Infection in ruminants was evaluated through inspection in local abattoirs, followed by molecular identification of one cyst per animal, with a priority for hepatic cysts, using PCR targeting of the cytochrome c oxidase I gene (COX1), followed by restriction fragment length polymorphism and multiplex PCR, and sequencing of non-E. granulosus s.l. samples. Results Ultrasound was performed on 823 volunteers (n = 352 in two villages in Longido District, and n = 471 in three villages of Ngorongoro). Hepatic CE cases were diagnosed only in Ngorongoro (n = 6; 1.3%), of which three had active cysts. Village-level prevalence of CE ranged between 0 and 2.4%. Of the 697 ruminants inspected, 34.4% had parasitic cysts. Molecular identification was achieved for 140 of the 219 (63.9%) cysts sampled. E. granulosus s.l. and T. hydatigena/Cysticercus tenuicollis were identified in 51.4% and 48.6%, respectively, of livestock cysts. E. granulosus s.l. was identified in livestock from both Longido (35.3% of 116 genotyped cysts) and Ngorongoro (91.2% of 34 genotyped cysts). Of the total of 72 E. granuslosus s.l. cysts identified in livestock, 87.5% were E. granulosus sensu strict o (G1–G3 genotypes), 9.7% were E. ortleppi (G5) and one cyst was E. canadensis (G6–10). The three active human cysts, which were removed surgically, were G1–G3 genotypes. Conclusions Multiple species/genotypes of E. granulosus s.l. are circulating in Maasai communities of northern Tanzania. Human CE was detected in villages of Ngorongoro District and a high prevalence of echinococcal cysts was observed in livestock in both districts. More precise estimation of the prevalence in this area and a better understanding of the specific risk factors for CE among Maasai communities in northern Tanzania is needed. Interventions targeting transmission routes common to both E. granulosus s.l. and T. multiceps would have dual benefits for preventing both human and livestock disease. Graphical Abstract
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- 2022
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12. Species and genotypes belonging to Echinococcus granulosussensu lato complex causing human cystic echinococcosis in Europe (2000–2021): a systematic review
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Casulli, Adriano, Massolo, Alessandro, Saarma, Urmas, Umhang, Gérald, Santolamazza, Federica, and Santoro, Azzurra
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- 2022
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13. Cystic echinococcosis in northern Tanzania: a pilot study in Maasai livestock-keeping communities
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Tamarozzi, Francesca, Kibona, Tito, de Glanville, William A., Mappi, Tauta, Adonikamu, Elly, Salewi, Anande, Misso, Kennedy, Maro, Venance, Casulli, Adriano, Santoro, Azzurra, Santolamazza, Federica, Mmbaga, Blandina T., and Cleaveland, Sarah
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- 2022
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14. Species and genotypes belonging to Echinococcus granulosus sensu lato complex causing human cystic echinococcosis in Europe (2000–2021): a systematic review
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Adriano Casulli, Alessandro Massolo, Urmas Saarma, Gérald Umhang, Federica Santolamazza, and Azzurra Santoro
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Echinococcus granulosus sensu lato ,Echinococcus granulosus sensu stricto ,Echinococcus canadensis ,Echinococcus ortleppi ,Genotypes ,Human cystic echinococcosis ,Infectious and parasitic diseases ,RC109-216 - Abstract
Abstract Background This study aimed to fill a gap of knowledge by providing a quantitative measure of molecularly identified species and genotypes belonging to Echinococcus granulosus sensu lato (s.l.) causing human cystic echinococcosis (CE) in Europe during the period 2000–2021. As these species and genotypes are characterized by genetic, animal host and geographical differences, studying the E. granulosus s.l. complex is epidemiologically relevant. Methods A systematic review (SR) was conducted on the basis of both scientific and grey literature considering primary studies between 2000 and 2021 in four databases. From a total of 1643 scientific papers, 51 records were included in the SR. The main inclusion criterion for this study was the molecular confirmation of E. granulosus s.l. at the genotype/species level as a causative agent of human CE cases in selected European countries. Results Relevant data were obtained from 29 out of 39 eligible European countries. This SR identified 599 human molecularly confirmed echinococcal cysts: 460 (76.8%) identified as E. granulosus sensu stricto (s.s.), 130 (21.7%) as E. canadensis cluster (G6/7 and G10), 7 (1.2%) as E. ortleppi (G5), and 2 as E. vogeli (0.3%). Three geographical hotspots of human CE caused by different species of the E. granulosus s.l. complex were identified: (1) E. granulosus s.s. in Southern and South-eastern Europe (European-Mediterranean and Balkan countries); (2) E. canadensis (G6/7) in Central and Eastern Europe; (3) E. ortleppi in Central and Western Europe. This SR also identified data gaps that prevented a better definition of the geographical distribution of the Echinococcus granulosus s.l. species complex in Europe: western Balkan countries, part of Central Europe, and Baltic countries. Conclusions These results mandate longitudinal, multi-centre, intersectoral and transdisciplinary studies which consider both molecular and clinical epidemiology in animals and humans. Such studies would be valuable for a better understanding of the transmission of the E. granulosus s.l. species complex and their potential clinical impact on humans. Graphical Abstract
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- 2022
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15. The Evolution of Energy Management Maturity in Organizations Subject to Mandatory Energy Audits: Findings from Italy
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Annalisa Santolamazza, Vito Introna, Vittorio Cesarotti, and Fabrizio Martini
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energy efficiency ,energy audit ,energy management ,maturity model ,energy efficiency directive ,Technology - Abstract
Promoting energy efficiency is a key element of the strategic commitment of the European Community. Prominent among the binding measures established by the 2012 Energy Efficiency Directive to further this vision is the requirement for large companies to conduct energy audits every four years. After receiving the second cycle of energy audit reports in December 2019, a new description of the energy situation of Italian companies was made available. This presented the previously inaccessible possibility of comparing the two situations reported in 2015 and 2019 to assess the development of energy efficiency practices in organizations subject to the legislative obligation of energy audits in the country. To this end, in collaboration with the Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), a project was initiated with the aim of developing the tools and methodologies necessary to assess in more detail the evolution that has occurred in the four years since 2015. In this paper, the findings of the analysis conducted on a significant sample of companies in Italy are presented. Through the design of a maturity model to assess the degree of progress achieved in a company’s energy management, the results of the two situations were analyzed. The analysis was deepened by assessing the progress achieved in different aspects of Energy Management: “Strategic Approach”, “Awareness, Competence, and Knowledge”, “Methodological Approach”, “Organizational Structure”, “Energy Performance Management and Information System”, and “Best Practices”. Furthermore, the observed variations were statistically tested using a pairwise t-test to make statistical inferences about the maturity of the total population of Italian enterprises under legislative obligation. The results have shown an increase in overall energy management maturity in each maturity dimension.
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- 2023
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16. Ectomycorrhizal fungal community structure in a young orchard of grafted and ungrafted hybrid chestnut saplings
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Santolamazza-Carbone, Serena, Iglesias-Bernabé, Laura, Sinde-Stompel, Esteban, and Gallego, Pedro Pablo
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- 2021
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17. The Agile Alert System For Gamma-Ray Transients
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Bulgarelli, A., Trifoglio, M., Gianotti, F., Tavani, M., Parmiggiani, N., Fioretti, V., Chen, A. W., Vercellone, S., Pittori, C., Verrecchia, F., Lucarelli, F., Santolamazza, P., Fanari, G., Giommi, P., Beneventano, D., Argan, A., Trois, A., Scalise, E., Longo, F., Pellizzoni, A., Pucella, G., Colafrancesco, S., Conforti, V., Tempesta, P., Cerone, M., Sabatini, P., Annoni, G., Valentini, G., and Salotti, L.
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Astrophysics - Instrumentation and Methods for Astrophysics ,Astrophysics - High Energy Astrophysical Phenomena - Abstract
In recent years, a new generation of space missions offered great opportunities of discovery in high-energy astrophysics. In this article we focus on the scientific operations of the Gamma-Ray Imaging Detector (GRID) onboard the AGILE space mission. The AGILE-GRID, sensitive in the energy range of 30 MeV-30 GeV, has detected many gamma-ray transients of galactic and extragalactic origins. This work presents the AGILE innovative approach to fast gamma-ray transient detection, which is a challenging task and a crucial part of the AGILE scientific program. The goals are to describe: (1) the AGILE Gamma-Ray Alert System, (2) a new algorithm for blind search identification of transients within a short processing time, (3) the AGILE procedure for gamma-ray transient alert management, and (4) the likelihood of ratio tests that are necessary to evaluate the post-trial statistical significance of the results. Special algorithms and an optimized sequence of tasks are necessary to reach our goal. Data are automatically analyzed at every orbital downlink by an alert pipeline operating on different timescales. As proper flux thresholds are exceeded, alerts are automatically generated and sent as SMS messages to cellular telephones, e-mails, and push notifications of an application for smartphones and tablets. These alerts are crosschecked with the results of two pipelines, and a manual analysis is performed. Being a small scientific-class mission, AGILE is characterized by optimization of both scientific analysis and ground-segment resources. The system is capable of generating alerts within two to three hours of a data downlink, an unprecedented reaction time in gamma-ray astrophysics., Comment: 34 pages, 9 figures, 5 tables
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- 2014
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18. An updated list of AGILE bright gamma-ray sources and their variability in pointing mode
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Verrecchia, F., Pittori, C., Chen, A. W., Bulgarelli, A., Tavani, M., Lucarelli, F., Giommi, P., Vercellone, S., Pellizzoni, A., Giuliani, A., Longo, F., Barbiellini, G., Trifoglio, M., Gianotti, F., Argan, A., Antonelli, L. A., Caraveo, P., Cardillo, M., Cattaneo, P. W., Cocco, V., Colafrancesco, S., Contessi, T., Costa, E., Del Monte, E., De Paris, G., Di Cocco, G., Di Persio, G., Donnarumma, I., Evangelista, Y., Fanari, G., Feroci, M., Ferrari, A., Fiorini, M., Fornari, F., Fuschino, F., Froysland, T., Frutti, M., Galli, M., Labanti, C., Lapshov, I., Lazzarotto, F., Liello, F., Lipari, P., Mattaini, E., Marisaldi, M., Mastropietro, M., Mauri, A., Mauri, F., Mereghetti, S., Morelli, E., Moretti, E., Morselli, A., Pacciani, L., Perotti, F., Piano, G., Picozza, P., Pilia, M., Pontoni, C., Porrovecchio, G., Prest, M., Primavera, R., Pucella, G., Rapisarda, M., Rappoldi, A., Rossi, E., Rubini, A., Sabatini, S., Santolamazza, P., Soffitta, P., Stellato, S., Striani, E., Tamburelli, F., Traci, A., Trois, A., Vallazza, E., Vittorini, V., Zanello, D., Salotti, L., and Valentini, G.
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
We present a variability study of a sample of bright gamma-ray (30 MeV -- 50 GeV) sources. This sample is an extension of the first AGILE catalogue of gamma-ray sources (1AGL), obtained using the complete set of AGILE observations in pointing mode performed during a 2.3 year period from July 9, 2007 until October 30, 2009. The dataset of AGILE pointed observations covers a long time interval and its gamma-ray data archive is useful for monitoring studies of medium-to-high brightness gamma-ray sources. In the analysis reported here, we used data obtained with an improved event filter that covers a wider field of view, on a much larger (about 27.5 months) dataset, integrating data on observation block time scales, which mostly range from a few days to thirty days. The data processing resulted in a better characterized source list than 1AGL was, and includes 54 sources, 7 of which are new high galactic latitude (|BII| >= 5) sources, 8 are new sources on the galactic plane, and 20 sources from the previous catalogue with revised positions. Eight 1AGL sources (2 high-latitude and 6 on the galactic plane) were not detected in the final processing either because of low OB exposure and/or due to their position in complex galactic regions. We report the results in a catalogue of all the detections obtained in each single OB, including the variability results for each of these sources. In particular, we found that 12 sources out of 42 or 11 out of 53 are variable, depending on the variability index used, where 42 and 53 are the number of sources for which these indices could be calculated. Seven of the 11 variable sources are blazars, the others are Crab pulsar+nebula, LS I +61{\deg}303, Cyg X-3, and 1AGLR J2021+4030., Comment: 30 pages, 12 figures
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- 2013
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19. Calibration of AGILE-GRID with In-Flight Data and Monte Carlo Simulations
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Chen, Andrew W., Argan, A., Bulgarelli, A., Cattaneo, P. W., Contessi, T., Giuliani, A., Pittori, C., Pucella, G., Tavani, M., Trois, A., Verrecchia, F., Barbiellini, G., Caraveo, P., Colafrancesco, S., Costa, E., De Paris, G., Del Monte, E., Di Cocco, G., Donnarumma, I., Evangelista, Y., Ferrari, A., Feroci, M., Fioretti, V., Fiorini, M., Fuschino, F., Galli, M., Gianotti, F., Giommi, P., Giusti, M., Labanti, C., Lapshov, I., Lazzarotto, F., Lipari, P., Longo, F., Lucarelli, F., Marisaldi, M., Mereghetti, S., Morelli, E., Moretti, E., Morselli, A., Pacciani, L., Pellizzoni, A., Perotti, F., Piano, G., Picozza, P., Pilia, M., Prest, M., Rapisarda, M., Rappoldi, A., Rubini, A., Sabatini, S., Santolamazza, P., Soffitta, P., Striani, E., Trifoglio, M., Valentini, G., Vallazza, E., Vercellone, S., Vittorini, V., and Zanello, D.
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Astrophysics - Instrumentation and Methods for Astrophysics ,Astrophysics - High Energy Astrophysical Phenomena - Abstract
Context: AGILE is a gamma-ray astrophysics mission which has been in orbit since 23 April 2007 and continues to operate reliably. The gamma-ray detector, AGILE-GRID, has observed Galactic and extragalactic sources, many of which were collected in the first AGILE Catalog. Aims: We present the calibration of the AGILE-GRID using in-flight data and Monte Carlo simulations, producing Instrument Response Functions (IRFs) for the effective area A_eff), Energy Dispersion Probability (EDP), and Point Spread Function (PSF), each as a function of incident direction in instrument coordinates and energy. Methods: We performed Monte Carlo simulations at different gamma-ray energies and incident angles, including background rejection filters and Kalman filter-based gamma-ray reconstruction. Long integrations of in-flight observations of the Vela, Crab and Geminga sources in broad and narrow energy bands were used to validate and improve the accuracy of the instrument response functions. Results: The weighted average PSFs as a function of spectra correspond well to the data for all sources and energy bands. Conclusions: Changes in the interpolation of the PSF from Monte Carlo data and in the procedure for construction of the energy-weighted effective areas have improved the correspondence between predicted and observed fluxes and spectra of celestial calibration sources, reducing false positives and obviating the need for post-hoc energy-dependent scaling factors. The new IRFs have been publicly available from the Agile Science Data Centre since November 25, 2011, while the changes in the analysis software will be distributed in an upcoming release.
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- 2013
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20. Prognosis of patients with differentiated thyroid carcinomas having a preoperative cytological report of indeterminate at low or high risk. A multicenter study
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Trimboli, Pierpaolo, Palermo, Andrea, Deandrea, Maurilio, Piccardo, Arnoldo, Campennì, Alfredo, Valabrega, Stefano, Grani, Giorgio, Santolamazza, Giuliano, Bottoni, Gianluca, Barnabei, Agnese, Ramundo, Valeria, Lauretta, Rosa, Monte, Lavinia, Ferrarazzo, Giulia, Paone, Gaetano, Crosetto, Cecilia, Ruggeri, Rosaria Maddalena, Baldari, Sergio, Chiefari, Alfonsina, Vottari, Sebastiano, Giarnieri, Enrico, Perrella, Eleonora, Limone, Paolo, Durante, Cosimo, Giovanella, Luca, Appetecchia, Marialuisa, and Crescenzi, Anna
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- 2019
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21. Epidemiology, Clinical Characteristics, Diagnostic Work Up, and Treatment Options of Leishmania Infection in Kidney Transplant Recipients: A Systematic Review
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Evaldo Favi, Giuliano Santolamazza, Francesco Botticelli, Carlo Alfieri, Serena Delbue, Roberto Cacciola, Andrea Guarneri, and Mariano Ferraresso
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Leishmania ,Leishmaniasis ,kidney transplant ,allograft ,infection ,treatment ,Medicine - Abstract
Current knowledge on Leishmania infection after kidney transplantation (KT) is limited. In order to offer a comprehensive guide for the management of post-transplant Leishmaniasis, we performed a systematic review following the latest PRISMA Checklist and using PubMed, Scopus, and Embase as databases. No time restrictions were applied, including all English-edited articles on Leishmaniasis in KT recipients. Selected items were assessed for methodological quality using a modified Newcastle–Ottawa Scale. Given the nature and quality of the studies (case reports and retrospective uncontrolled case series), data could not be meta-analyzed. A descriptive summary was therefore provided. Eventually, we selected 70 studies, describing a total of 159 cases of Leishmaniasis. Most of the patients were adult, male, and Caucasian. Furthermore, they were frequently living or travelling to endemic regions. The onset of the disease was variable, but more often in the late transplant course. The clinical features were basically similar to those reported in the general population. However, a generalized delay in diagnosis and treatment could be detected. Bone marrow aspiration was the preferred diagnostic modality. The main treatment options included pentavalent antimonial and liposomal amphotericin B, both showing mixed results. Overall, the outcomes appeared as concerning, with several patients dying or losing their transplant.
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- 2022
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22. The characterization of the distant blazar GB6 J1239+0443 from flaring and low activity periods
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Pacciani, L., Donnarumma, I., Denney, K. D., Assef, R. J., Ikejiri, Y., Yamanaka, M., Uemura, M., Domingo, A., Giommi, P., Tarchi, A., Verrecchia, F., Longo, F., Rainó, S., Giusti, M., Vercellone, S., Chen, A. W., Striani, E., Vittorini, V., Tavani, M., Bulgarelli, A., Giuliani, A., Pucella, G., Argan, A., Barbiellini, G., Caraveo, P., Cattaneo, P. W., Colafrancesco, S., Costa, E., De Paris, G., Del Monte, E., Di Cocco, G., Evangelista, Y., Ferrari, A., Feroci, M., Fiorini, M., Fuschino, F., Galli, M., Gianotti, F., Labanti, C., Lapshov, I., Lazzarotto, F., Lipari, P., Marisaldi, M., Mereghetti, S., Morelli, E., Moretti, E., Morselli, A., Pellizzoni, A., Perotti, F., Piano, G., Picozza, P., Pilia, M., Prest, M., Rapisarda, M., Rappoldi, A., Rubini, A., Sabatini, S., Soffitta, P., Trifoglio, M., Trois, A., Vallazza, E., Zanello, D., Pittori, C., Santolamazza, P., Lucarelli, F., Salotti, L., and Valentini, G.
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Astrophysics - High Energy Astrophysical Phenomena ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
In 2008 AGILE and Fermi detected gamma-ray flaring activity from the unidentified EGRET source 3EG J1236+0457, recently associated with a flat spectrum radio quasar GB6 J1239+0443 at z=1.762. The optical counterpart of the gamma-ray source underwent a flux enhancement of a factor 15-30 in 6 years, and of ~10 in six months. We interpret this flare-up in terms of a transition from an accretion-disk dominated emission to a synchrotron-jet dominated one. We analysed a Sloan Digital Sky Survey (SDSS) archival optical spectrum taken during a period of low radio and optical activity of the source. We estimated the mass of the central black hole using the width of the CIV emission line. In our work, we have also investigated SDSS archival optical photometric data and UV GALEX observations to estimate the thermal-disk emission contribution of GB6 J1239+0443. Our analysis of the gamma-ray data taken during the flaring episodes indicates a flat gamma-ray spectrum, with an extension of up to 15 GeV, with no statistically-relevant sign of absorption from the broad line region, suggesting that the blazar-zone is located beyond the broad line region. This result is confirmed by the modeling of the broad-band spectral energy distribution (well constrained by the available multiwavelength data) of the flaring activity periods and by the accretion disk luminosity and black hole mass estimated by us using archival data., Comment: 30 pages, 7 figures, 4 tables MNRAS Accepted on 2012 June 18
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- 2012
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23. Galactic Sources Science With Agile: The Case Of The Carina Region
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Sabatini, S., Tavani, M., Pian, E., Bulgarelli, A., Caraveo, P., Viotti, R., Corcoran, M. F., Giuliani, A., Pittori, C., Verrecchia, F., Vercellone, S., Mereghetti, S., Argan, A., Barbiellini, G., Boffelli, F., Cattaneo, P. W., Chen, A. W., Cocco, V., D'Ammando, F., Costa, E., De Paris, G., Del Monte, E., Di Cocco, G., Donnarumma, I., Evangelista, Y., Ferrari, A., Feroci, M., Fiorini, M., Froysland, T., Fuschino, F., Galli, M., Gianotti, F., Labanti, C., Lapshov, I., Lazzarotto, F., Lipari, P., Longo, F., Marisaldi, M., Mastropietro, M., Morelli, E., Moretti, E., Morselli, A., Pacciani, L., Pellizzoni, A., Perotti, F., Piano, G., Picozza, P., Pilia, M., Porrovecchio, G., Pucella, G., Prest, M., Rapisarda, M., Rappoldi, A., Rubini, A., Soffitta, P., Trifoglio, M., Trois, A., Vallazza, E., Vittorini, V., Zambra, A., Zanello, D., Santolamazza, P., Giommi, P., Colafrancesco, S., Antonelli, L. A., and Salotti, L.
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
During its first 2 years of operation, the gamma-ray AGILE satellite accumulated an extensive dataset for the Galactic plane. The data have been monitored for transient sources and several gamma-ray sources were detected. Their variability and possible association were studied. In this talk we will focus on the results of extensive observations of the Carina Region during the time period 2007 July - 2009 January, for a total livetime of ~130 days. The region is extremely complex, hosting massive star formation, with the remarkable colliding wind binary Eta Carinae, massive star clusters and HII regions (e.g. NGC 3324, RCW49, Westerlund II) and a giant molecular cloud extending over 150 pc (between l=284.7 and l=289). The Carina Nebula itself is the largest and IR highest surface brightness nebula of the Southern emisphere. We monitored several gamma ray sources in the Carina Region. In particular we detect a gamma ray source (1AGL J1043-5931) consistent with the position of Eta Carinae and report a remarkable 2-days gamma-ray flaring episode from this source on 2008 Oct 11-13. If 1AGL J1043-5931 is associated with the Eta Car system, our data provides the long sought first detection above 100 MeV of a colliding wind binary., Comment: 5 pages, 5 figures, proceedings of RICAP 2009
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- 2012
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24. The flaring blazars of the first 1.5 years of the AGILE mission
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Pacciani, L., Bulgarelli, A., Chen, A. W., D'Ammando, F., Donnarumma, I., Giuliani, A., Longo, F., Pucella, G., Tavani, M., Vercellone, S., Vittorini, V., Argan, A., Barbiellini, G., Boffelli, F., Caraveo, P., Cattaneo, P. W., Cocco, V., Costa, E., De Paris, G., Del Monte, E., Di Cocco, G., Evangelista, Y., Ferrari, A., Feroci, M., Fiorini, M., Froysland, T., Fuschino, F., Galli, M., Gianotti, F., Labanti, C., Lapshov, I., Lazzarotto, F., Lipari, P., Marisaldi, M., Mastropietro, M., Mereghetti, S., Morelli, E., Moretti, E., Morselli, A., Pellizzoni, A., Perotti, F., Piano, G., Picozza, P., Pilia, M., Porrovecchio, G., Prest, M., Rapisarda, M., Rappoldi, A., Rubini, A., Sabatini, S., Soffitta, P., Trifoglio, M., Trois, A., Vallazza, E., Zambra, A., Zanello, D., Antonelli, L. A., Colafrancesco, S., Giommi, P., Pittori, C., Verrecchia, F., Santolamazza, P., and Salotti, L.
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
We report the AGILE gamma-ray observations and the results of the multiwavelength campaigns on seven flaring blazars detected by the mission: During two multiwavelength campaigns, we observed gamma-ray activity from two Flat Spectrum Radio Quasars of the Virgo region, e.g. 3C 279 and 3C 273 (the latter being the first extragalactic source simultaneously observed with the gamma-ray telescope and the hard X ray imager of the mission). Due to the large FOV of the AGILE/GRID instrument, we achieved an almost continuous coverage of the FSRQ 3C 454.3. The source showed flux above 10E-6 photons/cm2/s (E > 100 MeV) and showed day by day variability during all the AGILE observing periods. In the EGRET era, the source was found in high gamma-ray activity only once. An other blazar, PKS 1510-089 was frequently found in high gamma-ray activity. S5 0716+71, an intermediate BL Lac object, exhibited a very high gamma-ray activity and fast gamma-ray variability during a period of intense optical activity. We observed high gamma-ray activity from W Comae, a BL Lac object, and Mrk 421, an high energy peaked BL Lac object. For this source, a multiwavelength campaign from optical to TeV has been performed.
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- 2011
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25. The observation of Gamma Ray Bursts and Terrestrial Gamma-ray Flashes with AGILE
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Del Monte, E., Barbiellini, G., Fuschino, F., Giuliani, A., Longo, F., Marisaldi, M., Mereghetti, S., Moretti, E., Trifoglio, M., Vianello, G., Costa, E., Donnarumma, I., Evangelista, Y., Feroci, M., Galli, M., Lapshov, I., Lazzarotto, F., Lipari, P., Pacciani, L., Rapisarda, M., Soffitta, P., Tavani, M., Vercellone, S., Cutini, S., Boffelli, F., Bulgarelli, A., Caraveo, P., Cattaneo, P. W., Chen, A., Di Cocco, G., Gianotti, F., Labanti, C., Morselli, A., Pellizzoni, A., Perotti, F., Piano, G., Picozza, P., Pilia, M., Prest, M., Pucella, G., Rappoldi, A., Sabatini, S., Striani, E., Trois, A., Vallazza, E., Vittorini, V., Antonelli, L. A., Pittori, C., Preger, B., Santolamazza, P., Verrecchia, F., Giommi, P., and Salotti, L.
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
Since its early phases of operation, the AGILE mission is successfully observing Gamma Ray Bursts (GRBs) in the hard X-ray band with the SuperAGILE imager and in the MeV range with the Mini-Calorimeter. Up to now, three firm GRB detections were obtained above 25 MeV and some bursts were detected with lower statistical confidence in the same energy band. When a GRB is localized, either by SuperAGILE or Swift/BAT or INTEGRAL/IBIS or Fermi/GBM or IPN, inside the field of view of the Gamma Ray Imager of AGILE, a detection is searched for in the gamma ray band or an upper limit is provided. A promising result of AGILE is the detection of very short gamma ray transients, a few ms in duration and possibly identified with Terrestrial Gamma-ray Flashes. In this paper we show the current status of the observation of Gamma Ray Bursts and Terrestrial Gamma-ray Flashes with AGILE., Comment: Four pages and four figures
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- 2011
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26. First results about on-ground calibration of the Silicon Tracker for the AGILE satellite
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AGILE Collaboration, Cattaneo, P. W., Argan, A., Boffelli, F., Bulgarelli, A., Buonomo, B., Chen, A. W., D'Ammando, F., Froysland, T., Fuschino, F., Galli, M., Gianotti, F., Giuliani, A., Longo, F., Marisaldi, M., Mazzitelli, G., Pellizzoni, A., Prest, M., Pucella, G., Quintieri, L., Rappoldi, A., Tavani, M., Trifoglio, M., Trois, A., Valente, P., Vallazza, E., Vercellone, S., Zambra, A., Barbiellini, G., Caraveo, P., Cocco, V., Costa, E., De Paris, G., Del Monte, E., Di Cocco, G., Donnarumma, I., Evangelista, Y., Feroci, M., Ferrari, A., Fiorini, M., Labanti, C., Lapshov, I., Lazzarotto, F., Lipari, P., Mastropietro, M., Mereghetti, S., Morelli, E., Moretti, E., Morselli, A., Pacciani, L., Perotti, F., Piano, G., Picozza, P., Pilia, M., Porrovecchio, G., Rapisarda, M., Rubini, A., Sabatini, S., Soffitta, P., Striani, E., Vittorini, V., Zanello, D., Colafrancesco, S., Giommi, P., Pittori, C., Santolamazza, P., Verrecchia, F., and Salotti, L.
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Astrophysics - Instrumentation and Methods for Astrophysics ,Physics - Instrumentation and Detectors - Abstract
The AGILE scientific instrument has been calibrated with a tagged $\gamma$-ray beam at the Beam Test Facility (BTF) of the INFN Laboratori Nazionali di Frascati (LNF). The goal of the calibration was the measure of the Point Spread Function (PSF) as a function of the photon energy and incident angle and the validation of the Monte Carlo (MC) simulation of the silicon tracker operation. The calibration setup is described and some preliminary results are presented., Comment: Presented at the 2nd Roma International Conference on Astroparticle Physics 2009, Villa Mondragone, Rome, Italy, May 13-15 2009. Pages 6, Figures 10
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- 2011
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27. Characterization of a tagged $\gamma$-ray beam line at the DA$\Phi$NE Beam Test Facility
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Cattaneo, P. W., Argan, A., Boffelli, F., Bulgarelli, A., Buonomo, B., Chen, A. W., D'Ammando, F., Froysland, T., Fuschino, F., Galli, M., Gianotti, F., Giuliani, A., Longo, F., Marisaldi, M., Mazzitelli, G., Pellizzoni, A., Prest, M., Pucella, G., Quintieri, L., Rappoldi, A., Tavani, M., Trifoglio, M., Trois, A., Valente, P., Vallazza, E., Vercellone, S., Zambra, A., Barbiellini, G., Caraveo, P., Cocco, V., Costa, E., De Paris, G., Del Monte, E., Di Cocco, G., Donnarumma, I., Evangelista, Y., Feroci, M., Ferrari, A., Fiorini, M., Labanti, C., Lapshov, I., Lazzarotto, F., Lipari, P., Mastropietro, M., Mereghetti, S., Morelli, E., Moretti, E., Morselli, A., Pacciani, L., Perotti, F., Piano, G., Picozza, P., Pilia, M., Porrovecchio, G., Rapisarda, M., Rubini, A., Sabatini, S., Soffitta, P., Striani, E., Vittorini, V., Zanello, D., Colafrancesco, S., Giommi, P., Pittori, C., Santolamazza, P., Verrecchia, F., and Salotti, L.
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Physics - Instrumentation and Detectors ,Astrophysics - Instrumentation and Methods for Astrophysics - Abstract
At the core of the AGILE scientific instrument, designed to operate on a satellite, there is the Gamma Ray Imaging Detector (GRID) consisting of a Silicon Tracker (ST), a Cesium Iodide Mini-Calorimeter and an Anti-Coincidence system of plastic scintillator bars. The ST needs an on-ground calibration with a $\gamma$-ray beam to validate the simulation used to calculate the energy response function and the effective area versus the energy and the direction of the $\gamma$ rays. A tagged $\gamma$-ray beam line was designed at the Beam Test Facility (BTF) of the INFN Laboratori Nazionali of Frascati (LNF), based on an electron beam generating $\gamma$ rays through bremsstrahlung in a position-sensitive target. The $\gamma$-ray energy is deduced by difference with the post-bremsstrahlung electron energy \cite{prest}-\cite{hasan}. The electron energy is measured by a spectrometer consisting of a dipole magnet and an array of position sensitive silicon strip detectors, the Photon Tagging System (PTS). The use of the combined BTF-PTS system as tagged photon beam requires understanding the efficiency of $\gamma$-ray tagging, the probability of fake tagging, the energy resolution and the relation of the PTS hit position versus the $\gamma$-ray energy. This paper describes this study comparing data taken during the AGILE calibration occurred in 2005 with simulation., Comment: 23 pages; 17 figures. Second and final version accepted by Nucl. Instr. & Meth. A
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- 2011
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28. AGILE detection of Cygnus X-3 {\gamma}-ray active states during the period mid-2009/mid-2010
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Bulgarelli, A., Tavani, M., Chen, A. W., Evangelista, Y., Trifoglio, M., Gianotti, F., Piano, G., Sabatini, S., Striani, E., Pooley, G., Trushkin, S., Nizhelskij, N. A., McCollough, M., Koljonen, K. I. I., Hannikainen, D., Lähteenmäki, A., Tammi, J., Lavonen, N., Steeghs, D., Aboudan, A., Argan, A., Barbiellini, G., Campana, R., Caraveo, P., Cattaneo, P. W., Cocco, V., Contessi, T., Costa, E., D'Ammando, F., Del Monte, E., De Paris, G., Di Cocco, G., Donnarumma, I., Feroci, M., Fiorini, M., Fuschino, F., Galli, M., Giuliani, A., Giusti, M., Labanti, C., Lapshov, I., Lazzarotto, F., Lipari, P., Longo, F., Marisaldi, M., Mereghetti, S., Morelli, E., Moretti, E., Morselli, A., Pacciani, L., Pellizzoni, A., Perotti, F., Picozza, P., Pilia, M., Prest, M., Pucella, G., Rapisarda, M., Rappoldi, A., Rubini, A., Soffitta, P., Trois, A., Vallazza, E., Vercellone, S., Vittorini, V., Zambra, A., Zanello, D., Giommi, P., Pittori, C., Verrecchia, F., Santolamazza, P., Lucarelli, F., Colafrancesco, S., and Salotti, L.
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
Cygnus X-3 (Cyg X-3) is a well-known microquasar producing variable emission at all wavelengths. Cyg X-3 is a prominent X-ray binary producing relativistic jets, and studying its high energy emission is crucial for the understanding of the fundamental acceleration processes in accreting compact objects. Aims. Our goal is to study extreme particle acceleration and {\gamma}-ray production above 100 MeV during special spectral states of Cyg X- 3 usually characterized by a low hard X-ray flux and enhanced soft X-ray states. We observed Cyg X-3 with the AGILE satellite in extended time intervals from 2009 Jun.-Jul., and 2009 Nov.-2010 Jul. We report here the results of the AGILE {\gamma}-ray monitoring of Cyg X-3 as well as the results from extensive multiwavelength campaigns involving radio (RATAN-600, AMI-LA and Mets\"{a}hovi Radio Observatories) and X-ray monitoring data (XTE and Swift). We detect a series of repeated {\gamma}-ray flaring activity from Cyg X-3 that correlate with the soft X-ray states and episodes of decreasing or non-detectable hard X-ray emission. Furthermore, we detect {\gamma}-ray enhanced emission that tends to be associated with radio flares greater than 1 Jy at 15 GHz, confirming a trend already detected in previous observations. The source remained active above 100 MeV for an extended period of time (almost 1.5 months in 2009 Jun.-Jul. and 1 month in 2010 May). We study in detail the short timescale {\gamma}-ray flares that occurred before or near the radio peaks. Our results confirm the transient nature of the extreme particle acceleration from the microquasar Cyg X-3. A series of repeated {\gamma}-ray flares shows correlations with radio and X-ray emission confirming a well established trend of emission. We compare our results with Fermi-LAT and MAGIC TeV observations of Cyg X-3., Comment: 16 pages, 8 figures, 7 tables; A&A (2011)
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- 2011
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29. The AGILE observations of the hard and bright GRB 100724B
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Del Monte, E., Barbiellini, G., Donnarumma, I., Fuschino, F., Giuliani, A., Longo, F., Marisaldi, M., Pucella, G., Tavani, M., Trifoglio, M., Trois, A., Argan, A., Bulgarelli, A., Caraveo, P., Cattaneo, P. W., Chen, A., Costa, E., D'Ammando, F., Di Cocco, G., Evangelista, Y., Feroci, M., Galli, M., Gianotti, F., Labanti, C., Lapshov, I., Lazzarotto, F., Lipari, P., Mereghetti, S., Moretti, E., Morselli, A., Pacciani, L., Pellizzoni, A., Perotti, F., Piano, G., Picozza, P., Pilia, M., Prest, M., Rapisarda, M., Rappoldi, A., Sabatini, S., Soffitta, P., Striani, E., Vallazza, E., Vercellone, S., Vittorini, V., Antonelli, L. A., Cutini, S., Pittori, C., Santolamazza, P., Verrecchia, F., Giommi, P., and Salotti, L.
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
The observation of Gamma Ray Bursts (GRBs) in the gamma-ray band has been advanced by the AGILE and Fermi satellites after the era of the Compton Gamma-Ray Observatory. AGILE and Fermi are showing that the GeV-bright GRBs share a set of common features, particularly the high fluence from the keV up to the GeV energy bands, the high value of the minimum Lorentz factor, the presence of an extended emission of gamma-rays, often delayed with respect to lower energies, and finally the possible presence of multiple spectral components. GRB 100724B, localised in a joint effort by Fermi and the InterPlanetary Newtork, is the brightest burst detected in gamma-rays so far by AGILE. Characteristic features of GRB 100724B are the simultaneous emissions at MeV and GeV, without delayed onset nor time lag as shown by the analysis of the cross correlation function, and the significant spectral evolution in hard X-rays over the event duration. In this paper we show the analysis of the AGILE data of GRB 100724B and we discuss its features in the context of the bursts observed so far in gamma-rays and the recently proposed models., Comment: 8 pages, 5 figures. Accepted for publication by A&A. Final version after the correction by the language editor
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- 2011
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30. The brightest gamma-ray flaring blazar in the sky: AGILE and multi-wavelength observations of 3C 454.3 during November 2010
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Vercellone, S., Striani, E., Vittorini, V., Donnarumma, I., Pacciani, L., Pucella, G., Tavani, M., Raiteri, C. M., Villata, M., Romano, P., Fiocchi, M., Bazzano, A., Bianchin, V., Ferrigno, C., Maraschi, L., Pian, E., Türler, M., Ubertini, P., Bulgarelli, A., Chen, A. W., Giuliani, A., Longo, F., Barbiellini, G., Cardillo, M., Cattaneo, P. W., Del Monte, E., Evangelista, Y., Feroci, M., Ferrari, A., Fuschino, F., Gianotti, F., Giusti, M., Lazzarotto, F., Pellizzoni, A., Piano, G., Pilia, M., Rapisarda, M., Rappoldi, A., Sabatini, S., Soffitta, P., Trifoglio, M., Trois, A., Giommi, P., Lucarelli, F., Pittori, C., Santolamazza, P., Verrecchia, F., Agudo, I., Aller, H. D., Aller, M. F., Arkharov, A. A., Bach, U., Berdyugin, A., Borman, G. A., Chigladze, R., Efimov, Yu. S., Efimova, N. V., Gómez, J. L., Gurwell, M. A., McHardy, I. M., Joshi, M., Kimeridze, G. N., Krajci, T., Kurtanidze, O. M., Kurtanidze, S. O., Larionov, V. M., Lindfors, E., Molina, S. N., Morozova, D. A., Nazarov, S. V., Nikolashvili, M. G., Nilsson, K., Pasanen, M., Reinthal, R., Ros, J. A., Sadun, A. C., Sakamoto, T., Sallum, S., Sergeev, S. G., Schwartz, R. D., Sigua, L. A., Sillanpää, A., Sokolovsky, K. V., Strelnitski, V., Takalo, L., Taylor, B., and Walker, G.
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
Since 2005, the blazar 3C 454.3 has shown remarkable flaring activity at all frequencies, and during the last four years it has exhibited more than one gamma-ray flare per year, becoming the most active gamma-ray blazar in the sky. We present for the first time the multi-wavelength AGILE, SWIFT, INTEGRAL, and GASP-WEBT data collected in order to explain the extraordinary gamma-ray flare of 3C 454.3 which occurred in November 2010. On 2010 November 20 (MJD 55520), 3C 454.3 reached a peak flux (E>100 MeV) of F_gamma(p) = (6.8+-1.0)E-5 ph/cm2/s on a time scale of about 12 hours, more than a factor of 6 higher than the flux of the brightest steady gamma-ray source, the Vela pulsar, and more than a factor of 3 brighter than its previous super-flare on 2009 December 2-3. The multi-wavelength data make a thorough study of the present event possible: the comparison with the previous outbursts indicates a close similarity to the one that occurred in 2009. By comparing the broadband emission before, during, and after the gamma-ray flare, we find that the radio, optical and X-ray emission varies within a factor 2-3, whereas the gamma-ray flux by a factor of 10. This remarkable behavior is modeled by an external Compton component driven by a substantial local enhancement of soft seed photons., Comment: Accepted for publication in ApJ Letters. 18 Pages, 4 Figures, 1 Table
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- 2011
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31. The Crab Nebula super-flare in April 2011: extremely fast particle acceleration and gamma-ray emission
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Striani, E., Tavani, M., Piano, G., Donnarumma, I., Pucella, G., Vittorini, V., Bulgarelli, A., Trois, A., Pittori, C., Verrecchia, F., Costa, E., Weisskopf, M., Tennant, A., Argan, A., Barbiellini, G., Caraveo, P., Cardillo, M, Cattaneo, P. W., Chen, A. W., De Paris, G., Del Monte, E., Di Cocco, G., Evangelista, Y., Ferrari, A., Feroci, M., Fuschino, F., Galli, M., Gianotti, F., Giuliani, A., Labanti, C., Lapshov, I., Lazzarotto, F., Longo, F., Marisaldi, M., Mereghetti, S., Morselli, A., Pacciani, L., Pellizzoni, A., Perotti, F., Picozza, P., Pilia, M., Rapisarda, M., Rappoldi, A., Sabatini, S., Soffitta, P., Trifoglio, M., Vercellone, S., Lucarelli, F., Santolamazza, P., and Giommi, P.
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
We report on the extremely intense and fast gamma-ray are above 100 MeV detected by AGILE from the Crab Nebula in mid-April 2011. This event is the fourth of a sequence of reported major gamma-ray flares produced by the Crab Nebula in the period 2007/mid-2011. These events are attributed to strong radiative and plasma instabilities in the inner Crab Nebula, and their properties are crucial for theoretical studies of fast and efficient particle acceleration up to 10^15 eV. Here we study the very rapid flux and spectral evolution of the event that reached on April 16, 2011 the record-high peak flux of F = (26 +/- 5) x 10^-6 ph cm^-2 s^-1 with a risetime timescale that we determine to be in the range 6-10 hrs. The peak flaring gamma-ray spectrum reaches a distinct maximum near 500 MeV with no substantial emission above 1 GeV. The very rapid risetime and overall evolution of the Crab Nebula are strongly constrain the acceleration mechanisms and challenge MHD models. We briefly discuss the theoretical implications of our observations., Comment: 4 pages, 2 figures. Accepted for pubblication in ApJL
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- 2011
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32. AGILE detection of extreme gamma-ray activity from the blazar PKS 1510-089 during March 2009. Multifrequency analysis
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D'Ammando, F., Raiteri, C. M., Villata, M., Romano, P., Pucella, G., Krimm, H. A., Covino, S., Orienti, M., Giovannini, G., Vercellone, S., Pian, E., Donnarumma, I., Vittorini, V., Tavani, M., Argan, A., Barbiellini, G., Boffelli, F., Bulgarelli, A., Caraveo, P., Cattaneo, P. W., Chen, A. W., Cocco, V., Costa, E., Del Monte, E., De Paris, G., Di Cocco, G., Evangelista, Y., Feroci, M., Ferrari, A., Fiorini, M., Froysland, T., Frutti, M., Fuschino, F., Galli, M., Gianotti, F., Giuliani, A., Labanti, C., Lapshov, I., Lazzarotto, F., Lipari, P., Longo, F., Marisaldi, M., Mereghetti, S., Morselli, A., Pacciani, L., Pellizzoni, A., Perotti, F., Piano, G., Picozza, P., Pilia, M., Porrovecchio, G., Prest, M., Rapisarda, M., Rappoldi, A., Rubini, A., Sabatini, S., Soffitta, P., Striani, E., Trifoglio, M., Trois, A., Vallazza, E., Zambra, A., Zanello, D., Agudo, I., Aller, H. D., Aller, M. F., Arkharov, A. A., Bach, U., Benitez, E., Berdyugin, A., Blinov, D. A., Buemi, C. S., Chen, W. P., Di Paola, A., Dolci, M., Forne, E., Fuhrmann, L., Gomez, J. L., Gurwell, M. A., Jordan, B., Jorstad, S. G., Heidt, J., Hiriart, D., Hovatta, T., Hsiao, H. Y., Kimeridze, G., Konstantinova, T. S., Kopatskaya, E. N., Koptelova, E., Kurtanidze, O. M., Kurtanidze, S. O., Larionov, V. M., Lahteenmaki, A., Leto, P., Lindfors, E., Marscher, A. P., McBreen, B., McHardy, I. M., Morozova, D. A., Nilsson, K., Pasanen, M., Roca-Sogorb, M., Sillanpaa, A., Takalo, L. O., Tornikoski, M., Trigilio, C., Troitsky, I. S., Umana, G., Antonelli, L. A., Colafrancesco, S., Pittori, C., Santolamazza, P., Verrecchia, F., Giommi, P., and Salotti, L.
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
We report on the extreme gamma-ray activity from the FSRQ PKS 1510-089 observed by AGILE in March 2009. In the same period a radio-to-optical monitoring of the source was provided by the GASP-WEBT and REM. Moreover, several Swift ToO observations were triggered, adding important information on the source behaviour from optical/UV to hard X-rays. We paid particular attention to the calibration of the Swift/UVOT data to make it suitable to the blazars spectra. Simultaneous observations from radio to gamma rays allowed us to study in detail the correlation among the emission variability at different frequencies and to investigate the mechanisms at work. In the period 9-30 March 2009, AGILE detected an average gamma-ray flux of (311+/-21)x10^-8 ph cm^-2 s^-1 for E>100 MeV, and a peak level of (702+/-131)x10^-8 ph cm^-2 s^-1 on daily integration. The gamma-ray activity occurred during a period of increasing activity from near-IR to UV, with a flaring episode detected on 26-27 March 2009, suggesting that a single mechanism is responsible for the flux enhancement observed from near-IR to UV. By contrast, Swift/XRT observations seem to show no clear correlation of the X-ray fluxes with the optical and gamma-ray ones. However, the X-ray observations show a harder photon index (1.3-1.6) with respect to most FSRQs and a hint of harder-when-brighter behaviour, indicating the possible presence of a second emission component at soft X-ray energies. Moreover, the broad band spectrum from radio-to-UV confirmed the evidence of thermal features in the optical/UV spectrum of PKS 1510-089 also during high gamma-ray state. On the other hand, during 25-26 March 2009 a flat spectrum in the optical/UV energy band was observed, suggesting an important contribution of the synchrotron emission in this part of the spectrum during the brightest gamma-ray flare, therefore a significant shift of the synchrotron peak., Comment: 13 pages, 7 figures, 3 tables. Accepted for publication in Astronomy and Astrophysics
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- 2011
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33. Discovery of Powerful Gamma-Ray Flares from the Crab Nebula
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Tavani, M., Bulgarelli, A., Vittorini, V., Pellizzoni, A., Striani, E., Caraveo, P., Weisskopf, M. C., Tennant, A., Pucella, G., Trois, A., Costa, E., Evangelista, Y., Pittori, C., Verrecchia, F., Del Monte, E., Campana, R., Pilia, M., De Luca, A., Donnarumma, I., Horns, D., Ferrigno, C., Heinke, C. O., Trifoglio, M., Gianotti, F., Vercellone, S., Argan, A., Barbiellini, G., Cattaneo, P. W., Chen, A. W., Contessi, T., D'Ammando, F., DeParis, G., Di Cocco, G., Di Persio, G., Feroci, M., Ferrari, A., Galli, M., Giuliani, A., Giusti, M., Labanti, C., Lapshov, I., Lazzarotto, F., Lipari, P., Longo, F., Fuschino, F., Marisaldi, M., Mereghetti, S., Morelli, E., Moretti, E., Morselli, A., Pacciani, L., Perotti, F., Piano, G., Picozza, P., Prest, M., Rapisarda, M., Rappoldi, A., Rubini, A., Sabatini, S., Soffitta, P., Vallazza, E., Zambra, A., Zanello, D., Lucarelli, F., Santolamazza, P., Giommi, P., Salotti, L., and Bignami, G. F.
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
The well known Crab Nebula is at the center of the SN1054 supernova remnant. It consists of a rotationally-powered pulsar interacting with a surrounding nebula through a relativistic particle wind. The emissions originating from the pulsar and nebula have been considered to be essentially stable. Here we report the detection of strong gamma-ray (100 MeV-10 GeV) flares observed by the AGILE satellite in September, 2010 and October, 2007. In both cases, the unpulsed flux increased by a factor of 3 compared to the non-flaring flux. The flare luminosity and short timescale favor an origin near the pulsar, and we discuss Chandra Observatory X-ray and HST optical follow-up observations of the nebula. Our observations challenge standard models of nebular emission and require power-law acceleration by shock-driven plasma wave turbulence within a ~1-day timescale., Comment: 23 pages (including Supporting On-line Material), 8 figures, 1 table. Version published in Science Express on January 6, 2011 (available at http://www.sciencemag.org/content/early/2011/01/05/science.1200083)
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- 2011
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34. Gamma-Ray Localization of Terrestrial Gamma-Ray Flashes
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Marisaldi, M., Argan, A., Trois, A., Giuliani, A., Tavani, M., Labanti, C., Fuschino, F., Bulgarelli, A., Longo, F., Barbiellini, G., Del Monte, E., Moretti, E., Trifoglio, M., Costa, E., Caraveo, P., Cattaneo, P. W., Chen, A., D'Ammando, F., De Paris, G., Di Cocco, G., Di Persio, G., Donnarumma, I., Evangelista, Y., Feroci, M., Ferrari, A., Fiorini, M., Froysland, T., Galli, M., Gianotti, F., Lapshov, I., Lazzarotto, F., Lipari, P., Mereghetti, S., Morselli, A., Pacciani, L., Pellizzoni, A., Perotti, F., Picozza, P., Piano, G., Pilia, M., Prest, M., Pucella, G., Rapisarda, M., Rappoldi, A., Rubini, A., Sabatini, S., Soffitta, P., Striani, E., Vallazza, E., Vercellone, S., Vittorini, V., Zambra, A., Zanello, D., Antonelli, L. A., Colafrancesco, S., Cutini, S., Giommi, P., Lucarelli, F., Pittori, C., Santolamazza, P., Verrecchia, F., and Salotti, L.
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Physics - Atmospheric and Oceanic Physics ,Astrophysics - Earth and Planetary Astrophysics - Abstract
Terrestrial Gamma-Ray Flashes (TGFs) are very short bursts of high energy photons and electrons originating in Earth's atmosphere. We present here a localization study of TGFs carried out at gamma-ray energies above 20 MeV based on an innovative event selection method. We use the AGILE satellite Silicon Tracker data that for the first time have been correlated with TGFs detected by the AGILE Mini-Calorimeter. We detect 8 TGFs with gamma-ray photons of energies above 20 MeV localized by the AGILE gamma-ray imager with an accuracy of 5-10 degrees at 50 MeV. Remarkably, all TGF-associated gamma rays are compatible with a terrestrial production site closer to the sub-satellite point than 400 km. Considering that our gamma rays reach the AGILE satellite at 540 km altitude with limited scattering or attenuation, our measurements provide the first precise direct localization of TGFs from space., Comment: 5 pages, 4 figures, 1 table, available at http://prl.aps.org/abstract/PRL/v105/i12/e128501
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- 2010
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35. Study of the gamma-ray source 1AGL J2022+4032 in the Cygnus Region
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Chen, A. W., Piano, G., Tavani, M., Trois, A., Dubner, G., Giacani, E., Argan, A., Barbiellini, G., Bulgarelli, A., Caraveo, P., Cattaneo, P. W., Costa, E., D'Ammando, F., De Paris, G., Del Monte, E., Di Cocco, G., Donnarumma, I., Evangelista, Y., Feroci, M., Ferrari, A., Fiorini, M., Fuschino, F., Galli, M., Gianotti, F., Giuliani, A., Giusti, M., Labanti, C., Lazzarotto, F., Lipari, P., Longo, F., Marisaldi, M., Mereghetti, S., Moretti, E., Morselli, A., Pacciani, L., Pellizzoni, A., Perotti, F., Picozza, P., Pilia, M., Prest, M., Pucella, G., Rapisarda, M., Rappoldi, A., Sabatini, S., Scalise, E., Soffitta, P., Striani, E., Trifoglio, M., Vallazza, E., Vercellone, S., Vittorini, V., Zambra, A., Zanello, D., Pittori, C., Giommi, P., Verrecchia, F., Lucarelli, F., Santolamazza, P., Colafrancesco, S., Antonelli, L. A., and Salotti, L.
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
Identification of gamma-ray-emitting Galactic sources is a long-standing problem in astrophysics. One such source, 1AGL J2022+4032, coincident with the interior of the radio shell of the supernova remnant Gamma Cygni (SNR G78.2+2.1) in the Cygnus Region, has recently been identified by Fermi as a gamma-ray pulsar, LAT PSR J2021+4026. We present long-term observations of 1AGL J2022+4032 with the AGILE gamma-ray telescope, measuring its flux and light curve. We compare the light curve of 1AGL J2022+4032 with that of 1AGL J2021+3652 (PSR J2021+3651), showing that the flux variability of 1AGL J2022+4032 appears to be greater than the level predicted from statistical and systematic effects and producing detailed simulations to estimate the probability of the apparent observed variability. We evaluate the possibility that the gamma-ray emission may be due to the superposition of two or more point sources, some of which may be variable, considering a number of possible counterparts. We consider the possibility of a nearby X-ray quiet microquasar contributing to the flux of 1AGL J2022+4032 to be more likely than the hypotheses of a background blazar or intrinsic gamma-ray variabilty of LAT PSR J2021+4026., Comment: 7 pages, 7 figures, accepted for publication in Astronomy & Astrophysics
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- 2010
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36. Agile Observations of the 'Soft' Gamma-Ray Pulsar PSR B1509-58
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Pilia, M., Pellizzoni, A., Trois, A., Verrecchia, F., Esposito, P., Weltevrede, P., Johnston, S., Burgay, M., Possenti, A., Del Monte, E., Fuschino, F., Santolamazza, P., Chen, A., Giuliani, A., Caraveo, P., Mereghetti, S., Tavani, M., Argan, A., Costa, E., D'Amico, N., De Luca, A., Evangelista, Y., Feroci, M., Longo, F., Marisaldi, M., Barbiellini, G., Bulgarelli, A., Cattaneo, P. W., Cocco, V., D'Ammando, F., De Paris, G., Di Cocco, G., Donnarumma, I., Fiorini, M., Froysland, T., Galli, M., Gianotti, F., Labanti, C., Lapshov, I., Lazzarotto, F., Lipari, P., Morselli, A., Pacciani, L., Perotti, F., Piano, G., Picozza, P., Prest, M., Pucella, G., Rapisarda, M., Rappoldi, A., Sabatini, S., Soffitta, P., Trifoglio, M., Vallazza, E., Vercellone, S., Vittorini, V., Zambra, A., Zanello, D., Pittori, C., Lucarelli, F., Giommi, P., Salotti, L., and Bignami, G. F.
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
We present the results of new Agile observations of PSR B1509-58 performed over a period of 2.5 years following the detection obtained with a subset of the present data. The modulation significance of the lightcurve above 30 MeV is at a 5$\sigma$ confidence level and the lightcurve is similar to those found earlier by Comptel up to 30 MeV: a broad asymmetric first peak reaching its maximum 0.39 +/- 0.02 cycles after the radio peak plus a second peak at 0.94 +/- 0.03. The gamma-ray spectral energy distribution of the pulsed flux detected by Comptel and Agile is well described by a power-law (photon index alpha=1.87+/-0.09) with a remarkable cutoff at E_c=81 +/- 20 MeV, representing the softest spectrum observed among gamma-ray pulsars so far. The pulsar luminosity at E > 1 MeV is $L_{\gamma}=4.2^{+0.5}_{-0.2} \times10^{35}$ erg/s, assuming a distance of 5.2 kpc, which implies a spin-down conversion efficiency to gamma-rays of $\sim 0.03$. The unusual soft break in the spectrum of PSR B1509-58 has been interpreted in the framework of polar cap models as a signature of the exotic photon splitting process in the strong magnetic field of this pulsar. In this interpretation our spectrum constrains the magnetic altitude of the emission point(s) at 3 km above the neutron star surface, implying that the attenuation may not be as strong as formerly suggested because pair production can substitute photon splitting in regions of the magnetosphere where the magnetic field becomes too low to sustain photon splitting. In the case of an outer-gap scenario, or the two pole caustic model, better constraints on the geometry of the emission would be needed from the radio band in order to establish whether the conditions required by the models to reproduce Agile lightcurves and spectra match the polarization measurements., Comment: 17 pages, 2 figures, accepted for publication in ApJ
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- 2010
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37. The extraordinary gamma-ray flare of the blazar 3C 454.3
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Striani, E., Vercellone, S., Tavani, M., Vittorini, V., D'Ammando, F., Donnarumma, I., Pacciani, L., Pucella, G., Bulgarelli, A., Trifoglio, M., Gianotti, F., Giommi, P., Argan, A., Barbiellini, G., Caraveo, P., Cattaneo, P. W., Chen, A. W., Costa, E., De Paris, G., Del Monte, E., Di Cocco, G., Evangelista, Y., Feroci, M., Ferrari, A., Fiorini, M., Fuschino, F., Galli, M., Giuliani, A., Giusti, M., Labanti, C., Lazzarotto, F., Lipari, P., Longo, F., Marisaldi, M., Mereghetti, S., Moretti, E., Morselli, A., Pellizzoni, A., Perotti, F., Piano, G., Picozza, P., Pilia, M., Prest, M., Rapisarda, M., Rappoldi, A., Sabatini, S., Scalise, E., Soffitta, P., Trois, A., Vallazza, E., Zambra, A., Zanello, D., Pittori, C., Verrecchia, F., Santolamazza, P., Lucarelli, F., Colafrancesco, S., Antonelli, L. A., and Salotti, L.
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Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We present the gamma-ray data of the extraordinary flaring activity above 100 MeV from the flat spectrum radio quasar 3C 454.3 detected by AGILE during the month of December 2009. 3C 454.3, that has been among the most active blazars of the FSRQ type since 2007, was detected in the gamma-ray range with a progressively rising flux since November 10, 2009. The gamma-ray flux reached a value comparable with that of the Vela pulsar on December 2, 2009. Remarkably, between December 2 and 3, 2009 the source more than doubled its gamma-ray emission and became the brightest gamma-ray source in the sky with a peak flux of F_{\gamma,p} = (2000 \pm 400) x 10^-8 ph cm^-2 s^-1 for a 1-day integration above 100 MeV. The gamma-ray intensity decreased in the following days with the source flux remaining at large values near F \simeq (1000 \pm 200) x 10^-8 ph cm^-2 s^-1 for more than a week. This exceptional gamma-ray flare dissipated among the largest ever detected intrinsic radiated power in gamma-rays above 100 MeV (L_{\gamma, source, peak} \simeq 3 x 10^46 erg s^-1, for a relativistic Doppler factor of {\delta} \simeq 30). The total isotropic irradiated energy of the month-long episode in the range 100 MeV - 3 GeV is E_{\gamma,iso} \simeq 10^56 erg. We report the intensity and spectral evolution of the gamma-ray emission across the flaring episode. We briefly discuss the important theoretical implications of our detection., Comment: 17 pages, 3 figures, ApJ accepted
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- 2010
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38. The December 2009 gamma-ray flare of 3C 454.3: the multifrequency campaign
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Pacciani, L., Vittorini, V., Tavani, M., Fiocchi, M. T., Vercellone, S., D'Ammando, F., Sakamoto, T., Pian, E., Raiteri, C. M., Villata, M., Sasada, M., Itoh, R., Yamanaka, M., Uemura, M., Striani, E., Fugazza, D., Tiengo, A., Krimm, H. A., Stroh, M. C., Falcone, A. D., Curran, P. A., Sadun, A. C., Lahteenmaki, A., Tornikoski, M., Aller, H. D., Aller, M. F., Lin, C. S., Larionov, V. M., Leto, P., Takalo, L. O., Berdyugin, A., Gurwell, M. A., Bulgarelli, A., Chen, A. W., Donnarumma, I., Giuliani, A., Longo, F., Pucella, G., Argan, A., Caraveo, G. Barbiellini P., Cattaneo, P. W., Cocco, V., Costa, E., De Paris, G., Del Monte, E., Di Cocco, G., Evangelista, Y., Ferrari, A., Feroci, M., Fiorini, M., Fuschino, F., Galli, M., Gianotti, F., Labanti, C., Lapshov, I., Lazzarotto, F., Lipari, P., Marisaldi, M., Mereghetti, S., Morelli, E., Moretti, E., Morselli, A., Pellizzoni, A., Perotti, F., Piano, G., Picozza, P., Pilia, M., Prest, M., Rapisarda, M., Rappoldi, A., Rubini, A., Sabatini, S., Soffitta, P., Trifoglio, M., Trois, A., Vallazza, E., Zanello, D., Colafrancesco, S., Pittori, C., Verrecchia, F., Santolamazza, P., Lucarelli, F., Giommi, P., and Salotti, L.
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Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
During the month of December, 2009 the blazar 3C 454.3 became the brightest gamma-ray source in the sky, reaching a peak flux F ~2000E-8 ph/cm2/s for E > 100 MeV. Starting in November, 2009 intensive multifrequency campaigns monitored the 3C 454 gamma-ray outburst. Here we report the results of a 2-month campaign involving AGILE, INTEGRAL, Swift/XRT, Swift/BAT, RossiXTE for the high-energy observations, and Swift/UVOT, KANATA, GRT, REM for the near-IR/optical/UV data. The GASP/WEBT provided radio and additional optical data. We detected a long-term active emission phase lasting ~1 month at all wavelengths: in the gamma-ray band, peak emission was reached on December 2-3, 2009. Remarkably, this gamma-ray super-flare was not accompanied by correspondingly intense emission in the optical/UV band that reached a level substantially lower than the previous observations in 2007-2008. The lack of strong simultaneous optical brightening during the super-flare and the determination of the broad-band spectral evolution severely constrain the theoretical modelling. We find that the pre- and post-flare broad-band behavior can be explained by a one-zone model involving SSC plus external Compton emission from an accretion disk and a broad-line region. However, the spectra of the Dec. 2-3, 2009 super-flare and of the secondary peak emission on Dec. 9, 2009 cannot be satisfactorily modelled by a simple one-zone model. An additional particle component is most likely active during these states., Comment: 21 pages, 2 figures, ApJL accepted
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- 2010
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39. AGILE detection of GeV gamma-ray emission from the SNR W28
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Giuliani, A., Tavani, M., Bulgarelli, A., Striani, E., Sabatini, S., Cardillo, M., Fukui, Y., Kawamura, A., Ohama, A., Furukawa, N., Torii, K., Aharonian, F. A., Verrecchia, F., Argan, A., Barbiellini, G., Caraveo, P. A., Cattaneo, P. W., Chen, A. W., Cocco, V., Costa, E., D'Ammando, F., Del Monte, E., De Paris, G., Di Cocco, G., Donnarumma, I., Evangelista, Y., Feroci, M., Fiorini, M., Froysland, T., Fuschino, F., Galli, M., Gianotti, F., Labanti, C., Lapshov, Y., Lazzarotto, F., Lipari, P., Longo, F., Mereghetti, M. Marisaldi., Morselli, A., Moretti, E., Pacciani, L., Pellizzoni, A., Perotti, F., Picozza, P., Pilia, M., Prest, M., Pucella, G., Rapisarda, M., Rappoldi, A., Soffitta, P., Trifoglio, M., Trois, A., Vallazza, E., Vercellone, S., Vittorini, V., Zambra, A., Zanello, D., Pittori, C., Santolamazza, P., Giommi, P., Colafrancesco, S., and Salotti, L.
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
Supernova remnants (SNRs) are believed to be the main sources of Galactic cosmic rays. Molecular clouds associated with SNRs can produce gamma-ray emission through the interaction of accelerated particles with the concentrated gas. The middle aged SNR W28, for its associated system of dense molecular clouds, provides an excellent opportunity to test this hypothesis. We present the AGILE/GRID observations of SNR W28, and compare them with observations at other wavelengths (TeV and 12CO J=1-->0 molecular line emission). The gamma-ray flux detected by AGILE from the dominant source associated with W28 is (14 +- 5) 10^-8 ph cm^-2 s^-1 for E > 400 MeV. This source is positionally well correlated with the TeV emission observed by the HESS telescope. The local variations of the GeV to TeV flux ratio suggest a difference between the CR spectra of the north-west and south molecular cloud complexes. A model based on a hadronic-induced interaction and diffusion with two molecular clouds at different distances from the W28 shell can explain both the morphological and spectral features observed by AGILE in the MeV-GeV energy range and by the HESS telescope in the TeV energy range. The combined set of AGILE and H.E.S.S. data strongly support a hadronic model for the gamma-ray production in W28., Comment: Accepted for publication in Astronomy & Astrophysics Letters
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- 2010
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40. A year-long AGILE observation of Cygnus X-1 in hard spectral state
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Del Monte, E., Feroci, M., Evangelista, Y., Costa, E., Donnarumma, I., Lapshov, I., Lazzarotto, F., Pacciani, L., Rapisarda, M., Soffitta, P., Argan, A., Barbiellini, G., Boffelli, F., Bulgarelli, A., Caraveo, P., Cattaneo, P. W., Chen, A., D'Ammando, F., Di Cocco, G., Fuschino, F., Galli, M., Gianotti, F., Giuliani, A., Labanti, C., Lipari, P., Longo, F., Marisaldi, M., Mereghetti, S., Moretti, E., Morselli, A., Pellizzoni, A., Perotti, F., Piano, G., Picozza, P., Pilia, M., Prest, M., Pucella, G., Rappoldi, A., Sabatini, S., Striani, E., Tavani, M., Trifoglio, M., Trois, A., Vallazza, E., Vercellone, S., Vittorini, V., Zambra, A., Antonelli, L. A., Cutini, S., Pittori, C., Preger, B., Santolamazza, P., Verrecchia, F., Giommi, P., and Salotti, L.
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
We present the observation of Cyg X-1 in hard spectral state performed during the AGILE Science Verification Phase and Observing Cycle 1 in hard X-rays (with SuperAGILE) and gamma rays (with the GRID) and lasting for about 160 days with a live time of $\sim 6$ Ms. We investigate the variability of Cyg X-1 in hard X-rays at different timescales, from $\sim 300$ s up to one day, and we apply different tools of timing analysis, such as the autocorrelation function, the first order structure function and the Lomb-Scargle periodogram, to our data (from SuperAGILE) and to the simultaneous data in soft X-rays (from RXTE/ASM). We conclude our investigation with a search for emission in the energy range above 100 MeV with the maximum likelihood technique. In the hard X-ray band the flux of Cyg X-1 shows its typical erratic fluctuations at all timescales with variations of about a factor of two that do not affect significantly the shape of the energy spectrum. From the first order structure function we find that the X-ray emission of Cyg X-1 is characterized by \textit{antipersistence}, indication of a negative feedback mechanism at work. In the gamma ray data a statistically significant point-like source at the position of Cyg X-1 is not found and the upper limit on the flux is $\mathrm{5 \times 10^{-8} \; ph \; cm^{-2} \; s^{-1}}$, over the whole observation (160 days). Finally we compare our upper limit in gamma rays with the expectation of various models of the Cyg X-1 emission, of both hadronic and leptonic origin, in the GeV -- TeV band. The time history of Cyg X-1 in the hard X-ray band over 13 months (not continuous) is shown. Different tools of analysis do not provide fully converging results of the characteristic timescales in the system, suggesting that the timescales found in the structure function are not intrinsic to the physics of the source., Comment: 15 pages and 11 figures (with subfigures). Accepted for publication by A&A.
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- 2010
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41. Episodic Transient Gamma-Ray Emission from the Microquasar Cygnus X-1
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Sabatini, S., Tavani, M., Striani, E., Bulgarelli, A., Vittorini, V., Piano, G., Del Monte, E., Feroci, M., de Pasquale, F., Trifoglio, M., Gianotti, F., Argan, A., Barbiellini, G., Caraveo, P., Cattaneo, P. W., Chen, A. W., D'Ammando, F., Costa, E., De Paris, G., Di Cocco, G., Donnarumma, I., Evangelista, Y., Ferrari, A., Fiorini, M., Fuschino, F., Galli, M., Giuliani, A., Giusti, M., Labanti, C., Lazzarotto, F., Lipari, P., Longo, F., Marisaldi, M., Mereghetti, S., Morelli, E., Moretti, E., Morselli, A., Pacciani, L., Pellizzoni, A., Perotti, F., Picozza, P., Pilia, M., Pucella, G., Prest, M., Rapisarda, M., Rappoldi, A., Rubini, A., Scalise, E., Soffitta, P., Trois, A., Vallazza, E., Vercellone, S., Zambra, A., Zanello, D., Pittori, C., Verrecchia, F., Santolamazza, P., Giommi, P., Colafrancesco, S., Antonelli, L. A., and Salotti, L.
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
Cygnus X-1 is the archetypal black hole (BH) binary system in our Galaxy. We report the main results of an extensive search for transient gamma-ray emission from Cygnus X-1 carried out in the energy range 100 MeV - 3 GeV by the AGILE satellite, during the period 2007 July - 2009 October. The total exposure time is about 300 days, during which the source was in the "hard" X-ray spectral state. We divided the observing intervals in 2 or 4 week periods, and searched for transient and persistent emission. We report an episode of significant transient gamma-ray emission detected on 2009, October 16 in a position compatible with Cygnus X-1 optical position. This episode, occurred during a hard spectral state of Cygnus X-1, shows that a 1-2 day time variable emission above 100 MeV can be produced during hard spectral states, having important theoretical implications for current Comptonization models for Cygnus X-1 and other microquasars. Except for this one short timescale episode, no significant gamma-ray emission was detected by AGILE. By integrating all available data we obtain a 2$\sigma$ upper limit for the total integrated flux of $F_{\gamma,U.L.} = 3 \times 10^{-8} \rm ph cm^{-2} s^{-1}$ in the energy range 100 MeV - 3 GeV. We then clearly establish the existence of a spectral cutoff in the energy range 1-100 MeV that applies to the typical hard state outside the flaring period and that confirms the historically known spectral cutoff above 1 MeV., Comment: Accepted for publication by ApJ on the 9th of Feb 2010, 5 pages, 3 figures
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- 2010
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42. Multiwavelength observations of 3C 454.3. III. Eighteen months of AGILE monitoring of the 'Crazy Diamond'
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Vercellone, S., D'Ammando, F., Vittorini, V., Donnarumma, I., Pucella, G., Tavani, M., Ferrari, A., Raiteri, C. M., Villata, M., Romano, P., Krimm, H., Tiengo, A., Chen, A. W., Giovannini, G., Venturi, T., Giroletti, M., Kovalev, Y. Y., Sokolovsky, K., Pushkarev, A. B., Lister, M. L., Argan, A., Barbiellini, G., Bulgarelli, A., Caraveo, P., Cattaneo, P. W., Cocco, V., Costa, E., Del Monte, E., De Paris, G., Di Cocco, G., Evangelista, Y., Feroci, M., Fiorini, M., Fornari, F., Froysland, T., Fuschino, F., Galli, M., Gianotti, F., Labanti, C., Lapshov, I., Lazzarotto, F., Lipari, P., Longo, F., Giuliani, A., Marisaldi, M., Mereghetti, S., Morselli, A., Pellizzoni, A., Pacciani, L., Perotti, F., Piano, G., Picozza, P., Pilia, M., Prest, M., Rapisarda, M., Rappoldi, A., Sabatini, S., Soffitta, P., Striani, E., Trifoglio, M., Trois, A., Vallazza, E., Zambra, A., Zanello, D., Pittori, C., Verrecchia, F., Santolamazza, P., Giommi, P., Colafrancesco, S., Salotti, L., Agudo, I., Aller, H. D., Aller, M. F., Arkharov, A. A., Bach, U., Bachev, R., Beltrame, P., Benitez, E., Boettcher, M., Buemi, C. S., Calcidese, P., Capezzali, D., Carosati, D., Chen, W. P., Da Rio, D., Di Paola, A., Dolci, M., Dultzin, D., Forne, E., Gomez, J. L., Gurwell, M. A., Hagen-Thorn, V. A., Halkola, A., Heidt, J., Hiriart, D., Hovatta, T., Hsiao, H. Y., Jorstad, S. G., Kimeridze, G., Konstantinova, T. S., Kopatskaya, E. N., Koptelova, E., Kurtanidze, O., Lahteenmaki, A., Larionov, V. M., Leto, P., Ligustri, R., Lindfors, E., Lopez, J. M., Marscher, A. P., Mujica, R., Nikolashvili, M., and Nilsson, K.
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
We report on 18 months of multiwavelength observations of the blazar 3C 454.3 (Crazy Diamond) carried out in July 2007-January 2009. We show the results of the AGILE campaigns which took place on May-June 2008, July-August 2008, and October 2008-January 2009. During the May 2008-January 2009 period, the source average flux was highly variable, from an average gamma-ray flux F(E>100MeV) > 200E-8 ph/cm2/s in May-June 2008, to F(E>100MeV)~80E-8 ph/cm2/s in October 2008-January 2009. The average gamma-ray spectrum between 100 MeV and 1 GeV can be fit by a simple power law (Gamma_GRID ~ 2.0 to 2.2). Only 3-sigma upper limits can be derived in the 20-60 keV energy band with Super-AGILE. During July-August 2007 and May-June 2008, RXTE measured a flux of F(3-20 keV)= 8.4E-11 erg/cm2/s, and F(3-20 keV)=4.5E-11 erg/cm2/s, respectively and a constant photon index Gamma_PCA=1.65. Swift/XRT observations were carried out during all AGILE campaigns, obtaining a F(2-10 keV)=(0.9-7.5)E-11 erg/cm2/s and a photon index Gamma_XRT=1.33-2.04. BAT measured an average flux of ~5 mCrab. GASP-WEBT monitored 3C 454.3 during the whole 2007-2008 period from the radio to the optical. A correlation analysis between the optical and the gamma-ray fluxes shows a time lag of tau=-0.4 days. An analysis of 15 GHz and 43 GHz VLBI core radio flux observations shows an increasing trend of the core radio flux, anti- correlated with the higher frequency data. The modeling SEDs, and the behavior of the long-term light curves in different energy bands, allow us to compare the jet properties during different emission states, and to study the geometrical properties of the jet on a time-span longer than one year., Comment: Accepted for publication in ApJ. Adapted Abstract. 17 pages, 19 Figures, 5 Tables
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- 2010
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43. Direct Evidence for Hadronic Cosmic-Ray Acceleration in the Supernova Renmant IC 443
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Tavani, M., Giuliani, A., Chen, A. W., Argan, A., Barbiellini, G., Bulgarelli, A., Caraveo, P., Cattaneo, P. W., Cocco, V., Contessi, T., D'Ammando, F., Costa, E., De Paris, G., Del Monte, E., Di Cocco, G., Donnarumma, I., Evangelista, Y., Ferrari, A., Feroci, M., Fuschino, F., Galli, M., Gianotti, F., Labanti, C., Lapshov, I., Lazzarotto, F., Lipari, P., Longo, F., Marisaldi, M., Mastropietro, M., Mereghetti, S., Morelli, E., Moretti, E., Morselli, A., Pacciani, L., Pellizzoni, A., Perotti, F., Piano, G., Picozza, P., Pilia, M., Pucella, G., Prest, M., Rapisarda, M., Rappoldi, A., Scalise, E., Rubini, A., Sabatini, S., Striani, E., Soffitta, P., Trifoglio, M., Trois, A., Vallazza, E., Vercellone, S., Vittorini, V., Zambra, A., Zanello, D., Pittori, C., Verrecchia, F., Santolamazza, P., Giommi, P., Colafrancesco, S., Antonelli, L. A., and Salotti, L.
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Astrophysics - High Energy Astrophysical Phenomena ,Astrophysics - Astrophysics of Galaxies - Abstract
The Supernova Remnant (SNR) IC 443 is an intermediate-age remnant well known for its radio, optical, X-ray and gamma-ray energy emissions. In this Letter we study the gamma-ray emission above 100 MeV from IC 443 as obtained by the AGILE satellite. A distinct pattern of diffuse emission in the energy range 100 MeV-3 GeV is detected across the SNR with its prominent maximum (source "A") localized in the Northeastern shell with a flux F = (47 \pm 10) 10^{-8} photons cm^{-2} s^{-1} above 100 MeV. This location is the site of the strongest shock interaction between the SNR blast wave and the dense circumstellar medium. Source "A" is not coincident with the TeV source located 0.4 degree away and associated with a dense molecular cloud complex in the SNR central region. From our observations, and from the lack of detectable diffuse TeV emission from its Northeastern rim, we demonstrate that electrons cannot be the main emitters of gamma-rays in the range 0.1-10 GeV at the site of the strongest SNR shock. The intensity, spectral characteristics, and location of the most prominent gamma-ray emission together with the absence of co-spatial detectable TeV emission are consistent only with a hadronic model of cosmic-ray acceleration in the SNR. A high-density molecular cloud (cloud "E") provides a remarkable "target" for nucleonic interactions of accelerated hadrons: our results show enhanced gamma-ray production near the molecular cloud/shocked shell interaction site. IC 443 provides the first unambiguous evidence of cosmic-ray acceleration by SNRs., Comment: 5 pages, 2 figures; accepted by ApJLetters on Jan 21, 2010
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- 2010
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44. Detection of Gamma-Ray Emission from the Vela Pulsar Wind Nebula with AGILE
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Pellizzoni, A., Trois, A., Tavani, M., Pilia, M., Giuliani, A., Pucella, G., Esposito, P., Sabatini, S., Piano, G., Argan, A., Barbiellini, G., Bulgarelli, A., Burgay, M., Caraveo, P., Cattaneo, P. W., Chen, A. W., Cocco, V., Contessi, T., Costa, E., D'Ammando, F., Del Monte, E., De Paris, G., Di Cocco, G., Di Persio, G., Donnarumma, I., Evangelista, Y., Feroci, M., Ferrari, A., Fiorini, M., Fuschino, F., Galli, M., Gianotti, F., Hotan, A., Labanti, C., Lapshov, I., Lazzarotto, F., Lipari, P., Longo, F., Marisaldi, M., Mastropietro, M., Mereghetti, S., Moretti, E., Morselli, A., Pacciani, L., Palfreyman, J., Perotti, F., Picozza, P., Pittori, C., Possenti, A., Prest, M., Rapisarda, M., Rappoldi, A., Rossi, E., Rubini, A., Santolamazza, P., Scalise, E., Soffitta, P., Striani, E., Trifoglio, M., Vallazza, E., Vercellone, S., Verrecchia, F., Vittorini, V., Zambra, A., Zanello, D., Giommi, P., Colafrancesco, S., Antonelli, A., Salotti, L., D'Amico, N., and Bignami, G. F.
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
Pulsars are known to power winds of relativistic particles that can produce bright nebulae by interacting with the surrounding medium. These pulsar wind nebulae (PWNe) are observed in the radio, optical, x-rays and, in some cases, also at TeV energies, but the lack of information in the gamma-ray band prevents from drawing a comprehensive multiwavelength picture of their phenomenology and emission mechanisms. Using data from the AGILE satellite, we detected the Vela pulsar wind nebula in the energy range from 100 MeV to 3 GeV. This result constrains the particle population responsible for the GeV emission, probing multivavelength PWN models, and establishes a class of gamma-ray emitters that could account for a fraction of the unidentified Galactic gamma-ray sources., Comment: Accepted by Science; first published online on December 31, 2009 in Science Express. Science article and Supporting Online Material are available at http://www.sciencemag.org
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- 2009
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45. Temporal properties of GX 301-2 over a year-long observation with SuperAGILE
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Evangelista, Y., Feroci, M., Costa, E., Del Monte, E., Donnarumma, I., Lapshov, I., Lazzarotto, F., Pacciani, L., Rapisarda, M., Soffitta, P., Argan, A., Barbiellini, G., Boffelli, F., Bulgarelli, A., Caraveo, P., Cattaneo, P. W., Chen, A., D'Ammando, F., Di Cocco, G., Fuschino, F., Galli, M., Gianotti, F., Giuliani, A., Labanti, C., Lipari, P., Longo, F., Marisaldi, M., Mereghetti, S., Moretti, E., Morselli, A., Pellizzoni, A., Perotti, F., Piano, G., Picozza, P., Pilia, M., Prest, M., Pucella, G., Rappoldi, A., Sabatini, S., Striani, E., Tavani, M., Trifoglio, M., Trois, A., Vallazza, E., Vercellone, S., Vittorini, V., Zambra, A., Antonelli, L. A., Cutini, S., Pittori, C., Preger, B., Santolamazza, P., Verrecchia, F., Giommi, P., and Salotti, L.
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
We present the long-term monitoring of the High Mass X-ray Binary GX 301-2 performed with the SuperAGILE instrument on-board the AGILE mission. The source was monitored in the 20-60 keV energy band during the first year of the mission from 2007 July 17 to 2008 August 31, covering about one whole orbital period and three more pre-periastron passages for a total net observation time of about 3.7 Ms. The SuperAGILE dataset represents one of the most continuous and complete monitoring at hard X-ray energies of the 41.5 day long binary period available to date. The source behavior was characterized at all orbital phases in terms of hard X-ray flux, spectral hardness, spin period history, pulsed fraction and pulse shape profile. We also complemented the SuperAGILE observations with the soft X-ray data of the RossiXTE/ASM. Our analysis shows a clear orbital modulation of the spectral hardness, with peaks in correspondence with the pre-periastron flare and near phase 0.25. The hardness peaks we found could be related with the wind-plus-stream accretion model proposed in order to explain the orbital light curve modulation of GX 301-2. Timing analysis of the pulsar spin period shows that the secular trend of the about 680 s pulse period is consistent with the previous observations, although there is evidence of a slight decrease in the spin-down rate. The analysis of the hard X-ray pulsed emission also showed a variable pulse shape profile as a function of the orbital phase, with substructures detected near the passage at the periastron, and a clear modulation of the pulsed fraction, which appears in turn strongly anti-correlated with the source intensity., Comment: 10 pages, 7 figures, 3 tables, accepted for publication in ApJ
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- 2009
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46. Discovery of extreme particle acceleration in the microquasar Cygnus X-3
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Tavani, M., Bulgarelli, A., Piano, G., Sabatini, S., Striani, E., Evangelista, Y., Trois, A., Pooley, G., Trushkin, S., Nizhelskij, N. A., McCollough, M., Koljonen, K. I. I., Pucella, G., Giuliani, A., Chen, A. W., Costa, E., Vittorini, V., Trifoglio, M., Gianotti, F., Argan, A., Barbiellini, G., Caraveo, P., Cattaneo, P. W., Cocco, V., Contessi, T., D'Ammando, F., Del Monte, E., De Paris, G., Di Cocco, G., Di Persio, G., Donnarumma, I., Feroci, M., Ferrari, A., Fuschino, F., Galli, M., Labanti, C., Lapshov, I., Lazzarotto, F., Lipari, P., Longo, F., Mattaini, E., Marisaldi, M., Mastropietro, M., Mauri, A., Mereghetti, S., Morelli, E., Morselli, A., Pacciani, L., Pellizzoni, A., Perotti, F., Picozza, P., Pilia, M., Prest, M., Rapisarda, M., Rappoldi, A., Rossi, E., Rubini, A., Scalise, E., Soffitta, P., Vallazza, E., Vercellone, S., Zambra, A., Zanello, D., Pittori, C., Verrecchia, F., Giommi, P., Colafrancesco, S., Santolamazza, P., Antonelli, A., and Salotti, L.
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Astrophysics - High Energy Astrophysical Phenomena ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
The study of relativistic particle acceleration is a major topic of high-energy astrophysics. It is well known that massive black holes in active galaxies can release a substantial fraction of their accretion power into energetic particles, producing gamma-rays and relativistic jets. Galactic microquasars (hosting a compact star of 1-10 solar masses which accretes matter from a binary companion) also produce relativistic jets. However, no direct evidence of particle acceleration above GeV energies has ever been obtained in microquasar ejections, leaving open the issue of the occurrence and timing of extreme matter energization during jet formation. Here we report the detection of transient gamma-ray emission above 100 MeV from the microquasar Cygnus X-3, an exceptional X-ray binary which sporadically produces powerful radio jets. Four gamma-ray flares (each lasting 1-2 days) were detected by the AGILE satellite simultaneously with special spectral states of Cygnus X-3 during the period mid-2007/mid-2009. Our observations show that very efficient particle acceleration and gamma-ray propagation out of the inner disk of a microquasar usually occur a few days before major relativistic jet ejections. Flaring particle energies can be thousands of times larger than previously detected maximum values (with Lorentz factors of 105 and 102 for electrons and protons, respectively). We show that the transitional nature of gamma-ray flares and particle acceleration above GeV energies in Cygnus X-3 is clearly linked to special radio/X-ray states preceding strong radio flares. Thus gamma-rays provide unique insight into the nature of physical processes in microquasars., Comment: 29 pages (including Supplementary Information), 8 figures, 2 tables version submitted to Nature on August 7, 2009 (accepted version available at http://www.nature.com/nature/journal/vaop/ncurrent/pdf/nature08578.pdf)
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- 2009
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47. Multiwavelength observations of 3C 454.3 II. The AGILE 2007 December campaign
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Donnarumma, I., Pucella, G., Vittorini, V., D'Ammando, F., Vercellone, S., Raiteri, C. M., Villata, M., Perri, M., Chen, W. P., Smart, R. L., Kataoka, J., Kawai, N., Mori, Y., Tosti, G., Impiombato, D., Takahashi, T., Sato, R., Tavani, M., Bulgarelli, A., Chen, A. W., Giuliani, A., Longo, F., Pacciani, L., Argan, A., Barbiellini, G., Boffelli, F., Caraveo, P., Cattaneo, P. W., Cocco, V., Contessi, T., Costa, E., Del Monte, E., De Paris, G., Di Cocco, G., Evangelista, Y., Feroci, M., Ferrari, A., Fiorini, M., Froysland, T., Frutti, M., Fuschino, F., Galli, M., Gianotti, F., Labanti, C., Lapshov, I., Lazzarotto, F., Lipari, P., Marisaldi, M., Mastropietro, M., Mereghetti, S., Morelli, E., Moretti, E., Morselli, A., Pellizzoni, A., Perotti, F., Picozza, P., Pilia, M., Porrovecchio, G., Prest, M., Rapisarda, M., Rappoldi, A., Rubini, A., Sabatini, S., Scalise, E., Soffitta, P., Striani, E., Trifoglio, M., Trois, A., Vallazza, E., Zambra, A., Zanello, D., Pittori, C., Santolamazza, P., Verrecchia, F., Giommi, P., Antonelli, L. A., Colafrancesco, S., and Salotti, L.
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Astrophysics - Cosmology and Nongalactic Astrophysics ,Astrophysics - High Energy Astrophysical Phenomena - Abstract
We report on the second AGILE multiwavelength campaign of the blazar 3C 454.3 during the first half of December 2007. This campaign involved AGILE, Spitzer, Swift,Suzaku,the WEBT consortium,the REM and MITSuME telescopes,offering a broad band coverage that allowed for a simultaneous sampling of the synchrotron and inverse Compton (IC) emissions.The 2-week AGILE monitoring was accompanied by radio to optical monitoring by WEBT and REM and by sparse observations in mid-Infrared and soft/hard X-ray energy bands performed by means of Target of Opportunity observations by Spitzer, Swift and Suzaku, respectively.The source was detected with an average flux of~250x10^{-8}ph cm^-2s^-1 above 100 MeV,typical of its flaring states.The simultaneous optical and gamma-ray monitoring allowed us to study the time-lag associated with the variability in the two energy bands, resulting in a possible ~1-day delay of the gamma-ray emission with respect to the optical one. From the simultaneous optical and gamma-ray fast flare detected on December 12, we can constrain the delay between the gamma-ray and optical emissions within 12 hours. Moreover, we obtain three Spectral Energy Distributions (SEDs) with simultaneous data for 2007 December 5, 13, 15, characterized by the widest multifrequency coverage. We found that a model with an external Compton on seed photons by a standard disk and reprocessed by the Broad Line Regions does not describe in a satisfactory way the SEDs of 2007 December 5, 13 and 15. An additional contribution, possibly from the hot corona with T=10^6 K surrounding the jet, is required to account simultaneously for the softness of the synchrotron and the hardness of the inverse Compton emissions during those epochs., Comment: 13 pages, 8 figures, 2 tables, Accepted for publication in ApJ
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- 2009
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48. Monitoring the hard X-ray sky with SuperAGILE
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Feroci, M., Costa, E., Del Monte, E., Donnarumma, I., Evangelista, Y., Lapshov, I., Lazzarotto, F., Pacciani, L., Rapisarda, M., Soffitta, P., Di Persio, G., Frutti, M., Mastropietro, M., Morelli, E., Porrovecchio, G., Rubini, A., Antonelli, A., Argan, A., Barbiellini, G., Boffelli, F., Bulgarelli, A., Caraveo, P., Cattaneo, P. W., Chen, A. W., Cocco, V., Colafrancesco, S., Cutini, S., D'Ammando, F., De Paris, G., Di Cocco, G., Fanari, G., Ferrari, A., Fiorini, M., Fornari, F., Fuschino, F., Froysland, T., Galli, M., Gasparrini, D., Gianotti, F., Giommi, P., Giuliani, A., Labanti, C., Liello, F., Lipari, P., Longo, F., Mattaini, E., Marisaldi, M., Mauri, A., Mauri, F., Mereghetti, S., Moretti, E., Morselli, A., Pellizzoni, A., Perotti, F., Piano, G., Picozza, P., Pilia, M., Pittori, C., Pontoni, C., Preger, B., Prest, M., Primavera, R., Pucella, G., Rappoldi, A., Rossi, E., Sabatini, S., Santolamazza, P., Tavani, M., Stellato, S., Tamburelli, F., Traci, A., Trifoglio, M., Trois, A., Vallazza, E., Vercellone, S., Verrecchia, F., Vittorini, V., Zambra, A., Zanello, D., and Salotti, L.
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Astrophysics - Instrumentation and Methods for Astrophysics ,Astrophysics - High Energy Astrophysical Phenomena - Abstract
SuperAGILE is the hard X-ray monitor of the AGILE gamma ray mission, in orbit since 23$^{rd}$ April 2007. It is an imaging experiment based on a set of four independent silicon strip detectors, equipped with one-dimensional coded masks, operating in the nominal energy range 18-60 keV. The main goal of SuperAGILE is the observation of cosmic sources simultaneously with the main gamma-ray AGILE experiment, the Gamma Ray Imaging Detector (GRID). Given its $\sim$steradian-wide field of view and its $\sim$15 mCrab day-sensitivity, SuperAGILE is also well suited for the long-term monitoring of Galactic compact objects and the detection of bright transients. The SuperAGILE detector properties and design allow for a 6 arcmin angular resolution in each of the two independent orthogonal projections of the celestial coordinates. Photon by photon data are continuously available by the experiment telemetry, and are used to derive images and fluxes of individual sources, with integration times depending on the source intensity and position in the field of view. In this paper we report on the main scientific results achieved by SuperAGILE over its first two years in orbit, until April 2009., Comment: Accepted for publication on Astronomy & Astrophysics
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- 2009
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49. Multiwavelength observations of a TeV-Flare from W Comae
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VERITAS collaboration, Acciari, V. A., Aliu, E., Aune, T., Beilicke, M., Benbow, W., Bottcher, M., Boltuch, D., Buckley, J. H., Bradbury, S. M., Bugaev, V., Byrum, K., Cannon, A., Cesarini, A., Ciupik, L., Cogan, P., Cui, W., Dickherber, R., Duke, C., Falcone, A., Finley, J. P., Fortin, P., Fortson, L., Furniss, A., Galante, N., Gall, D., Gibbs, K., Gillanders, G. H., Grube, J., Guenette, R., Gyuk, G., Hanna, D., Holder, J., Hui, C. M., Humensky, T. B., Kaaret, P., Karlsson, N., Kertzman, M., Kieda, D., Konopelko, A., Krawczynski, H., Krennrich, F., Lang, M. J., LeBohec, S., Maier, G., McArthur, S., McCann, A., McCutcheon, M., Millis, J., Moriarty, P., Ong, R. A., Otte, A. N., Pandel, D., Perkins, J. S., Pichel, A., Pohl, M., Quinn, J., Ragan, K., Reyes, L. C., Reynolds, P. T., Roache, E., Rose, H. J., Sembroski, G. H., Smith, A. W., Steele, D., Theiling, M., Thibadeau, S., Varlotta, A., Vassiliev, V. V., Vincent, S., Wakely, S. P., Ward, J. E., Weekes, T. C., Weinstein, A., Weisgarber, T., Williams, D. A., Wissel, S., Wood, M., Team, The AGILE, Pian, E., Vercellone, S., Donnarumma, I., D'Ammando, F., Bulgarelli, A., Chen, A. W., Giuliani, A., Longo, F., Pacciani, L., Pucella, G., Vittorini, V., Tavani, M., Argan, A., Barbiellini, G., Caraveo, P., Cattaneo, P. W., Cocco, V., Costa, E., Del Monte, E., De Paris, G., Di Cocco, G., Evangelista, Y., Feroci, M., Fiorini, M., Froysland, T., Frutti, M., Fuschino, F., Galli, M., Gianotti, F., Labanti, C., Lapshov, I., Lazzarotto, F., Lipari, P., Marisaldi, M., Mastropietro, M., Mereghetti, S., Morelli, E., Morselli, A., Pellizzoni, A., Perotti, F., Piano, G., Picozza, P., Pilia, M., Porrovecchio, G., Prest, M., Rapisarda, M., Rappoldi, A., Rubini, A., Soffitta, S. Sabatini P., Trifoglio, M., Trois, A., Vallazza, E., Zambra, A., Zanello, D., Pittori, C., Santolamazza, P., Verrecchia, F., Giommi, P., Colafrancesco, S., Salotti, L., Villata, M., Raiteri, C. M., Aller, H. D., Aller, M. F., Arkharov, A. A., Efimova, N. V., Larionov, V. M., Leto, P., Ligustri, R., Lindfors, E., Pasanen, M., Kurtanidze, O. M., Tetradze, S. D., Lahteenmaki, A., Kotiranta, M., Cucchiara, A., Romano, P., Nesci, R., Pursimo, T., Heidt, J., Benitez, E., Hiriart, D., Nilsson, K., Berdyugin, A., Mujica, R., Dultzin, D., Lopez, J. M., Mommert, M., Sorcia, M., and Perez, I. de la Calle
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
We report results from an intensive multiwavelength campaign on the intermediate-frequency-peaked BL Lacertae object W Com (z=0.102) during a strong outburst of very high energy gamma-ray emission in June 2008. The very high energy gamma-ray signal was detected by VERITAS on 2008 June 7-8 with a flux F(>200 GeV) = (5.7+-0.6)x10^-11 cm-2s-1, about three times brighter than during the discovery of gamma-ray emission from W Com by VERITAS in 2008 March. The initial detection of this flare by VERITAS at energies above 200 GeV was followed by observations in high energy gamma-rays (AGILE, E>100 MeV), and X-rays (Swift and XMM-Newton), and at UV, and ground-based optical and radio monitoring through the GASP-WEBT consortium and other observatories. Here we describe the multiwavelength data and derive the spectral energy distribution (SED) of the source from contemporaneous data taken throughout the flare., Comment: 26 pages, 5 figures; Accepted for publication by The Astrophysical Journal
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- 2009
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50. AGILE detection of a rapid gamma-ray flare from the blazar PKS 1510-089 during the GASP-WEBT monitoring
- Author
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D'Ammando, F., Pucella, G., Raiteri, C. M., Villata, M., Vittorini, V., Vercellone, S., Donnarumma, I., Longo, F., Tavani, M., Argan, A., Barbiellini, G., Boffelli, F., Bulgarelli, A., Caraveo, P., Cattaneo, P. W., Chen, A. W., Cocco, V., Costa, E., Del Monte, E., De Paris, G., Di Cocco, G., Evangelista, Y., Feroci, M., Ferrari, A., Fiorini, M., Froysland, T., Fuschino, F., Galli, M., Gianotti, F., Giuliani, A., Labanti, C., Lapshov, I., Lazzarotto, F., Lipari, P., Marisaldi, M., Mereghetti, S., Morselli, A., Pacciani, L., Pellizzoni, A., Perotti, F., Piano, G., Picozza, P., Pilia, M., Prest, M., Rapisarda, M., Rappoldi, A., Sabatini, S., Soffitta, P., Trifoglio, M., Trois, A., Vallazza, E., Zambra, A., Zanello, D., Agudo, I., Aller, M. F., Aller, H. D., Arkharov, A. A., Bach, U., Benitez, E., Berdyugin, A., Blinov, D. A., Buemi, C. S., Chen, W. P., Di Paola, A., Di Rico, G., Dultzin, D., Fuhrmann, L., Gomez, J. L., Gurwell, M. A., Jorstad, S. G., Heidt, J., Hiriart, D., Hsiao, H. Y., Kimeridze, G., Konstantinova, T. S., Kopatskaya, E. N., Koptelova, E., Kurtanidze, O., Larionov, V. M., Leto, P., Lindfors, E., Lopez, J. M., Marscher, A. P., McHardy, I. M., Melnichuk, D. A., Mommert, M., Mujica, R., Nilsson, K., Pasanen, M., Roca-Sogorb, M., Sorcia, M., Takalo, L. O., Taylor, B., Trigilio, C., Troitsky, I. S., Umana, G., Antonelli, L. A., Colafrancesco, S., Cutini, S., Gasparrini, D., Pittori, C., Preger, B., Santolamazza, P., Verrecchia, F., Giommi, P., and Salotti, L.
- Subjects
Astrophysics - High Energy Astrophysical Phenomena ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We report the detection by the AGILE satellite of a rapid gamma-ray flare from the powerful gamma-ray quasar PKS 1510-089, during a pointing centered on the Galactic Center region from 1 March to 30 March 2008. This source has been continuosly monitored in the radio-to-optical bands by the GLAST-AGILE Support Program (GASP) of the Whole Earth Blazar Telescope (WEBT). Moreover, the gamma-ray flaring episode triggered three ToO observations by the Swift satellite in three consecutive days, starting from 20 March 2008. In the period 1-16 March 2008, AGILE detected gamma-ray emission from PKS 1510-089 at a significance level of 6.2-sigma with an average flux over the entire period of (84 +/- 17) x 10^{-8} photons cm^{-2} s^{-1} for photon energies above 100 MeV. After a predefined satellite re-pointing, between 17 and 21 March 2008, AGILE detected the source at a significance level of 7.3-sigma, with an average flux (E > 100 MeV) of (134 +/- 29) x 10^{-8} photons cm^{-2} s^{-1} and a peak level of (281 +/- 68) x 10^{-8} photons cm^{-2} s^{-1} with daily integration. During the observing period January-April 2008, the source also showed an intense and variable optical activity, with several flaring episodes and a significant increase of the flux was observed at millimetric frequencies. Moreover, in the X-ray band the Swift/XRT observations seem to show an harder-when-brighter behaviour of the source spectrum. The spectral energy distribution of mid-March 2008 is modelled with a homogeneous one-zone synchrotron self Compton emission plus contributions from inverse Compton scattering of external photons from both the accretion disc and the broad line region. Indeed, some features in the optical-UV spectrum seem to indicate the presence of Seyfert-like components, such as the little blue bump and the big blue bump., Comment: 10 pages, 4 figures and 2 tables, accepted for publication in A&A
- Published
- 2009
- Full Text
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