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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').
Advanced Search

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"

11838 results found.

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

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