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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
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To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

5822 results found.

  1. IceCube-190503A: Lick/KAIT Follow-Up Observations
  2. LIGO/Virgo S190503bf: MAXI/GSC Observations
  3. LIGO/Virgo S190503bf: Identification of a GW compact binary merger candidate
  4. LIGO/Virgo S190412m: Further J-GEM optical/NIR observations
  5. LIGO/Virgo S190426c: PS1 historical detections and ZTF photometry of Gaia19boq AT2019egk
  6. Fermi GRB190429.74 Global MASTER-Net observations report
  7. LIGO/Virgo S190426c: YAHPT Optical Observation
  8. LIGO/Virgo S190425z: MASTER detection of the faint flare in SDSS Seyfert galaxy z = 0.09
  9. LIGO/Virgo S190426c: Continued LOAO Observation
  10. LIGO/Virgo S190425z: MASTER explanation of the nature of an optical flash detected by a Swift as a short flare on a fast-moving WISE brown
  11. LIGO/Virgo S190426c: LOAO Observation
  12. LIGO/Virgo S190425z: SVOM/GWAC-F60A observations
  13. LIGO/Virgo S190426c: DDOTI/OAN Optical Observations
  14. LIGO/Virgo S190425z: Pre-discovery NIR limits of the UVOT transient candidate from Gattini-IR
  15. LIGO/Virgo S190426c: RATIR Optical and NIR Observations of Galaxies
  16. LIGO/Virgo S190426c: COATLI Optical Observations of Galaxies
  17. GRB 190419A: AstroSat CZTI detection
  18. LIGO/Virgo S190426c: MMT Follow-Up Observations
  19. LIGO/Virgo S190426c: Lick/KAIT Follow-Up Observations
  20. LIGO/Virgo S190426c: Swift-XRT sources
  21. LIGO/Virgo S190425z: BOOTES-5/JGT observations of galaxies
  22. LIGO/Virgo S190425z: GRANDMA follow-up observations with Les Makes-T60, AZT-8 and Abastumani-T70
  23. LIGO/Virgo S190425z: Further MMT Follow-Up Observations
  24. Baksan Neutrino Observatory Alert 190405.62: Global MASTER-Net:LIGO/Virgo S190425z: PanSTARR OT AT2019ebq/PS19qp
  25. LIGO/Virgo S190425z: COATLI Observations of Galaxies
  26. LIGO/Virgo S190425z: RATIR Observations of Galaxies
  27. LIGO/Virgo S190425z: GROND observations of AT2019ebq/PS19qp
  28. LIGO/Virgo S190425z: TAROT-GRANDMA observation report
  29. LIGO/Virgo S190425z: Las Cumbres Observatory Galaxy Targeted Counterpart Search
  30. LIGO/Virgo S190425z: LWA1 observations
  31. LIGO/Virgo S190425z: KMTNet Observation
  32. LIGO/Virgo S190425z: Swope follow-up observations
  33. LIGO/Virgo S190425z: Pan-STARRS observations and transients in the skymap
  34. LIGO/Virgo S190425z: KPED Follow-Up Observations
  35. LIGO/Virgo S190425z: ATLAS observations of the S190425z skymap
  36. LIGO/Virgo S190425z: ZTF19aarzaod Imaging from Las Cumbres Observatory
  37. LIGO/Virgo S190425z: J-GEM optical follow-up observations with Subaru/FOCAS
  38. LIGO/Virgo S190425z: Candidates from the Zwicky Transient Facility
  39. LIGO/Virgo S190425z: Xinglong/Schmidt follow-up observations
  40. LIGO/Virgo S190425z: Palomar Gattini-IR wide-field infrared follow-up
  41. LIGO/Virgo S190425z: SQUEAN Observation
  42. LIGO/Virgo S190425z: Lick/KAIT Follow-Up Observations
  43. LIGO/Virgo S190425z: MAXI/GSC Observations
  44. LIGO/VIRGO S190425z: IceCube Neutrino Search
  45. LIGO/Virgo S190425z Global MASTER-Net observations report
  46. Fermi GRB190425.09 Global MASTER-Net observations report
  47. LIGO/Virgo S190421ar: TAROT-GRANDMA observation report.
  48. LIGO/Virgo S190421ar: Lick/KAIT Follow-Up Observations
  49. LIGO/Virgo S190421ar Global MASTER-Net observations report
  50. Konus-Wind observation of GRB 190415A
  51. Fermi GRB190420.98 Global MASTER-Net observations report
  52. Fermi GRB190419.41 Global MASTER-Net observations report
  53. Fermi Trigger 577360542 / GRB 190419414 / GRB190419A: BALROG localization
  54. IPN Triangulation of GRB 190415A
  55. GRB 190415A: Insight-HXMT/HE detection
  56. Fermi Trigger 576994194 / GRB 190415173 / : BALROG localization
  57. GRB 190411A: AstroSat CZTI detection
  58. LIGO/Virgo S190412m: Fermi-LAT search for a high-energy gamma-ray counterpart
  59. LIGO/Virgo S190408an: Pan-STARRS observations and transients in the skymap
  60. LIGO/Virgo S190408an: TMTS Optical Observation
  61. LIGO/Virgo S190408an: DDOTI/OAN Optical Observations
  62. LIGO/Virgo S190408an: HMT optical observations
  63. LIGO/Virgo S190408an: SAGUARO follow-up observations
  64. CORRECTED TARGET NAME: GRB 190408A: MAXI/GSC detection
  65. GRB 140408A: MAXI/GSC detection
  66. Search for neutrino counterparts to GW candidate S190408an with IceCube
  67. GRB 140404B: MAXI/GSC detection
  68. GRB 190330A: MITSuME Akeno and Okayama optical upper limits
  69. IceCube-190331A: MASTER optical follow-up observations
  70. IPN Triangulation of GRB 190329A (long/bright)
  71. Swift Trigger 895257: Detection of GRO J2058+42 in outburst
  72. GRB 190326A: Swift detection of a short burst
  73. Fermi Trigger 575108474 / GRB 190324348: BALROG localization
  74. Fermi Trigger 574678842 / GRB 190319375: BALROG localization
  75. Fermi trigger 574140965 / GRB190313.15: MASTER Global Robotic Net optical observation
  76. GRB190305A: MASTER Global Robotic Net optical observation
  77. GRB190219A: MASTER Global Robotic Net optical observation
  78. Trigger 889483: Swift detection of Swift J1858.6-0814
  79. Trigger 888312: Swift detection of 4U 1901+03
  80. GRB 190203A: COATLI Optical Observations
  81. GRB 190204A: Swift detection of a burst with a possible optical counterpart
  82. GRB 190203A: Swift detection of a burst with an optical counterpart
  83. GRB 190202A: Swift/UVOT Detection
  84. GRB 190202A: Koshka Zeiss-1000 optical observations
  85. GRB 190202A: Swift detection of a burst with an optical counterpart
  86. GRB 190129B: MASTER Global Robotic Net optical observation
  87. GRB 190129A: MAXI/GSC detection
  88. Trigger 886486: Swift detection of MAXI J1631-479
  89. Trigger 886266: Another Swift trigger on MAXI J1348-630
  90. Swift Trigger 886157: Swift detection of a new transient Swift J1728.9-3613
  91. INTEGRAL triggers from 8205 to 8211 are due to MAXI J1348-630, NOT to a GRB
  92. Swift Trigger 885960: A third Swift trigger on MAXI J1348-630
  93. Trigger 885845: A second Swift trigger on MAXI J1348-630
  94. GRB 190123A: IKI-GRB-FuN optical upper limit
  95. Trigger 884906: Swift detection of MAXI J1631-479
  96. GRB 190114A: Swift detection of a burst
  97. GRB 190109B: Fermi GBM observation
  98. GRB 190109A: Fermi GBM observation
  99. GRB 190109B: COATLI Optical Observations
  100. GRB 190109B: Mondy optical upper limit

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