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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

11844 results found.

  1. LIGO/Virgo S190513bm: Swope follow-up observations
  2. GRB 190515A: Fermi-LAT detection
  3. GRB 190515B: Swift detection of a burst
  4. LIGO/Virgo S190513bm: CALET Observations
  5. Fermi GRB190514.67 Global MASTER-Net observations report
  6. LIGO/Virgo S190513bm: Lick/KAIT Follow-Up Observations
  7. LIGO/Virgo S190510g: Gaia Photometric Alerts transient candidate
  8. LIGO/Virgo S190513bm: Insight-HXMT/HE observation
  9. LIGO/Virgo S190510g: Swift-XRT observations and results
  10. LIGO/Virgo S190513bm: ANTARES neutrino search
  11. Konus-Wind observation of GRB 190511A
  12. Konus-Wind observation of GRB 190510A
  13. LIGO/Virgo S190513bm: Fermi-LAT search for a high-energy gamma-ray counterpart
  14. LIGO/Virgo S190513bm: MAXI/GSC Observations
  15. LIGO/Virgo S190510g: Further KMTNet observation of DECam-GROWTH and DESGW candidates
  16. LIGO/Virgo S190513bm: AGILE GRID observations
  17. LIGO/Virgo S190513bm: INTEGRAL prompt observation
  18. LIGO/Virgo S190513bm: AGILE MCAL observation
  19. LIGO/Virgo S190513bm: IceCube Neutrino Search
  20. LIGO/Virgo S190513bm: HAWC follow-up
  21. LIGO/Virgo S190513bm: Identification of a GW compact binary merger candidate
  22. LIGO/Virgo S190512at: Fermi-LAT search for a high-energy gamma-ray counterpart
  23. LIGO/Virgo S190512at: MAXI/GSC Observations
  24. LIGO/Virgo S190512at Global MASTER-Net observations report
  25. Fermi GRB190512.61 Global MASTER-Net observations report
  26. GRB 190511A: Swift/UVOT Detection
  27. LIGO/Virgo S190510g: KMTNet observation of DECam-GROWTH and DESGW candidates
  28. GRB 190511A: NOT optical afterglow
  29. LIGO/Virgo S190510g: Las Cumbres Observatory Galaxy Targeted Counterpart Search
  30. LIGO/Virgo S190510g: GRAWITA REM and Loiano optical observations
  31. GRB 190511A: Fermi-LAT detection
  32. LIGO/Virgo S190510g : Xinglong-60cm upper limit of the GRAWITA REM's OT
  33. LIGO/Virgo S190510g: MASTER OT independ detection in WISE J060606.26-353233.9 galaxy at desgw-190510a position.
  34. LIGO/Virgo S190510g: Dabancheng/HMT Follow-Up Observations
  35. GRB 190511A: Swift detection of a burst
  36. LIGO/Virgo S190510g: CNEOST Follow-Up Observations
  37. LIGO/Virgo S190510g: Lick/KAIT Follow-Up Observations
  38. LIGO/Virgo S190510g: Lulin Optical Follow-up Observations
  39. LIGO/Virgo S190510g: Fermi-LAT search for a high-energy gamma-ray counterpart
  40. LIGO/Virgo S190510g: CLU/NED Galaxies in the Localization Volume
  41. Konus-Wind observation of GRB 190501A
  42. LIGO/Virgo S190510g: MAXI/GSC Observations
  43. LIGO/Virgo S190510g: HAWC follow-up
  44. Fermi GRB190510.12 Global MASTER-Net observations report
  45. GRB 190507B: GOTO optical counterpart search
  46. Fermi GRB190507.27 Global MASTER-Net observations report
  47. LIGO/Virgo S190426c: Konus-Wind observations
  48. LIGO/Virgo S190425z: Konus-Wind observations
  49. IceCube-190504A: MASTER optical monitoring analysis
  50. LIGO/Virgo S190503bf: AstroSat CZTI upper limits
  51. Fermi GRB190506.58 Global MASTER-Net observations report
  52. Search for additional neutrino events from the direction of IceCube-190504A with IceCube
  53. IceCube-190504A: Swift-XRT Follow-up Observations
  54. IceCube-190503A: Swift-XRT Follow-up Observations
  55. Fermi GRB190505.82 Global MASTER-Net observations report
  56. Fermi-LAT Gamma-ray Observations of IceCube-190504A
  57. Fermi GRB190505.05 Global MASTER-Net observations report
  58. Fermi GRB190504.68 Global MASTER-Net observations report
  59. LIGO/Virgo S190503bf Global MASTER-Net observations report
  60. IceCube-190503A: Lick/KAIT Follow-Up Observations
  61. LIGO/Virgo S190503bf: Fermi-LAT search for a high-energy gamma-ray counterpart
  62. Fermi-LAT Gamma-ray Observations of IceCube-190503A
  63. LIGO/Virgo S190503bf: MAXI/GSC Observations
  64. IceCube-190503A: INTEGRAL prompt observation
  65. IPN Triangulation of GRB 190501A (long/bright)
  66. GRB 190501A: GOTO optical counterpart search
  67. LIGO/Virgo S190425z: Insight-HXMT observation and counterpart search
  68. LIGO/Virgo S190425z: Gaia Photometric Alerts transient candidates
  69. GRB 190501A: AGILE/GRID detection
  70. LIGO/Virgo S190426c: Gaia Photometric Alerts transient candidate
  71. LIGO/Virgo S190426c: Swift rapid follow-up observations of S190425z and S190426c and URL for observation log for all future events
  72. LIGO/Virgo S190412m: Further J-GEM optical/NIR observations
  73. LIGO/Virgo S190426c: YAHPT Optical Observation
  74. LIGO/Virgo S190426c: Fermi-LAT search for a high-energy gamma-ray counterpart
  75. LIGO/Virgo S190426c: MASTER analysys of GRAWITA transients
  76. LIGO/Virgo S190426c: GRAWITA transients from Asiago Schmidt wide field observations
  77. LIGO/Virgo S190426c: OAJ-GRANDMA observation report
  78. LIGO/Virgo S190425z: No i-band detection of the Swift/UVOT transient in SkyMapper observations
  79. LIGO/Virgo S190426c: DG19ytre and DG19kplb 1.5m OSN imaging and 10.4m GTC spectroscopy
  80. LIGO/Virgo S190425z: SVOM/GWAC-F60A observations
  81. LIGO/Virgo S190425z: Additional Candidates from the Zwicky Transient Facility
  82. LIGO/Virgo S190426c: DDOTI/OAN Optical Observations
  83. LIGO/Virgo S190426c: J-GEM optical/NIR follow-up observations
  84. LIGO/Virgo S190426c: COATLI Optical Observations of Galaxies
  85. LIGO/Virgo S190426c: MMT Follow-Up Observations
  86. LIGO/Virgo S190426c: GOTO optical coverage - no notable counterparts
  87. LIGO/Virgo S190426c: Lick/KAIT Follow-Up Observations
  88. LIGO/Virgo S190426c: CNEOST Optical Observations
  89. LIGO/Virgo S190425z: CNEOST Optical Observations
  90. LIGO/Virgo S190425z: Lulin Observations of Counterpart Search
  91. GRB 190427A: BOOTES-1 and BOOTES-5/JGT early follow-up observations
  92. LIGO/Virgo S190425z: BOOTES-5/JGT observations of galaxies
  93. LIGO/Virgo S190425z: Fermi-LAT search for a high-energy gamma-ray counterpart
  94. Swift GRB190427.19 Global MASTER-Net observations report
  95. GRB 190427A: Swift detection of a short burst
  96. LIGO/Virgo S190426c: MAXI/GSC Observations
  97. LIGO/Virgo S190425z: GRANDMA follow-up observations with Les Makes-T60, AZT-8 and Abastumani-T70
  98. LIGO/Virgo S190426c: SAO optical observation
  99. Baksan Neutrino Observatory Alert 190405.62: Global MASTER-Net:LIGO/Virgo S190425z: PanSTARR OT AT2019ebq/PS19qp
  100. LIGO/Virgo S190425z: COATLI Observations of Galaxies

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