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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"

2724 results found.

  1. Fermi trigger No 583567803 Global MASTER-Net observations report
  2. Fermi trigger No 583327924 Global MASTER-Net observations report
  3. GRB 190626B: Fermi GBM Final Real-time Localization
  4. Fermi trigger No 583111521 Global MASTER-Net observations report
  5. Fermi trigger No 582886211 Global MASTER-Net observations report
  6. Fermi trigger No 582856902 Global MASTER-Net observations report
  7. Fermi trigger No 582615488 Global MASTER-Net observations report
  8. GRB 190613B: AstroSat CZTI detection
  9. GRB 190611B: AstroSat CZTI detection
  10. Konus-Wind observation of GRB 190613B
  11. Fermi trigger No 582159815 Global MASTER-Net observations report
  12. GRB 190611B: CALET Gamma-Ray Burst Monitor detection
  13. GRB 190613B: Insight-HXMT/HE detection
  14. Konus-Wind observation of short/hard GRB 190610A
  15. Konus-Wind observation of GRB 190611B
  16. Fermi trigger No 582115625 Global MASTER-Net observations report
  17. GRB 190613B: Fermi GBM observation
  18. GRB 190611B: BALROG localization (Fermi Trigger 581986074 / GRB 190611950)
  19. IPN Triangulation of GRB 190611B
  20. GRB 190613B: BALROG localization (Fermi Trigger 582115625 / GRB 190613449)
  21. GRB 190613B: Swift detection of a burst with an optical counterpart
  22. GRB 190613B: Fermi GBM Final Real-time Localization
  23. GRB 190613A: Fermi GBM Final Real-time Localization
  24. GRB 190611B: Fermi GBM detection
  25. Fermi trigger No 581889628 Global MASTER-Net observations report
  26. Fermi trigger No 581882394 Global MASTER-Net observations report
  27. GRB 190609A: Fermi GBM Final Real-time Localization
  28. Fermi trigger No 581719018 Global MASTER-Net observations report
  29. Fermi trigger No 581645543 Global MASTER-Net observations report
  30. Fermi trigger No 581469752 Global MASTER-Net observations report
  31. GRB 190605A: Fermi GBM Final Real-time Localization
  32. Fermi trigger No 581281470 Global MASTER-Net observations report
  33. Konus-Wind observation of extremely bright GRB 190530A
  34. GRB 190525A: AstroSat CZTI detection
  35. LIGO/Virgo S190521r: CNEOST follow-up observations
  36. Fermi GRB190525.03 Global MASTER-Net observations report
  37. GRB 190525A: Fermi GBM Final Real-time Localization
  38. LIGO/Virgo S190521g: No optical counterpart from SVOM/GWAC observations.
  39. IGO/Virgo S190521g: Coverage and upper limits from MAXI/GSC observations
  40. LIGO/Virgo S190512at: SVOM/GWAC-F60A observations
  41. LIGO/Virgo S190519bj: MAXI/GSC Observations
  42. LIGO/Virgo S190519bj Global MASTER-Net observations report
  43. Fermi GRB190517.81 Global MASTER-Net observations report
  44. LIGO/Virgo S190513bm : TAROT-Calern and TAROT-Chile (TCA/TCH)/GRANDMA observation report.
  45. Fermi GRB190514.67 Global MASTER-Net observations report
  46. LIGO/Virgo S190513bm: Lick/KAIT Follow-Up Observations
  47. LIGO/Virgo S190510g: Further KMTNet observation of DECam-GROWTH and DESGW candidates
  48. LIGO/Virgo S190513bm Global MASTER-Net observations report
  49. LIGO/Virgo S190510g: Pan-STARRS and ATLAS observations and candidates
  50. LIGO/Virgo S190512at Global MASTER-Net observations report
  51. LIGO/Virgo S190510g: DOAO Observation
  52. LIGO/Virgo S190510g: KMTNet observation of DECam-GROWTH and DESGW candidates
  53. LIGO/Virgo S190510g: Las Cumbres Observatory Galaxy Targeted Counterpart Search
  54. LIGO/Virgo S190510g: Dabancheng/HMT Follow-Up Observations
  55. LIGO/Virgo S190510g: Xinglong/Schmidt Follow-Up Observations
  56. LIGO/Virgo S190510g: SOAR/Goodman follow-up observations
  57. LIGO/Virgo S190510g: CNEOST Follow-Up Observations
  58. LIGO/Virgo S190510g: Lick/KAIT Follow-Up Observations
  59. LIGO/Virgo S190510g: Lulin Optical Follow-up Observations
  60. LIGO/Virgo S190425z: CAHA-GRANDMA Observation of the Swift UVOT Source
  61. Konus-Wind observation of GRB 190501A
  62. LIGO/Virgo S190510g: HSC Y-band follow-up observation
  63. Fermi GRB190510.12 Global MASTER-Net observations report
  64. LIGO/Virgo S190510g Global MASTER-Net observations report
  65. Fermi GRB190507.97 Global MASTER-Net observations report
  66. Fermi GRB190507.27 Global MASTER-Net observations report
  67. IceCube-190504A: MASTER optical monitoring analysis
  68. Fermi GRB190505.05 Global MASTER-Net observations report
  69. Fermi GRB190504.68 Global MASTER-Net observations report
  70. LIGO/Virgo S190503bf Global MASTER-Net observations report
  71. IceCube-190503A: Lick/KAIT Follow-Up Observations
  72. Fermi GRB190429.74 Global MASTER-Net observations report
  73. LIGO/Virgo S190426c: YAHPT Optical Observation
  74. LIGO/Virgo S190426c: MASTER analysys of GRAWITA transients
  75. LIGO/Virgo S190426c: OAJ-GRANDMA observation report
  76. LIGO/Virgo S190426c: DDOTI/OAN Optical Observations
  77. LIGO/Virgo S190426c: COATLI Optical Observations of Galaxies
  78. LIGO/Virgo S190426c: MMT Follow-Up Observations
  79. LIGO/Virgo S190426c: Lick/KAIT Follow-Up Observations
  80. LIGO/Virgo S190426c: CNEOST Optical Observations
  81. LIGO/Virgo S190425z: CNEOST Optical Observations
  82. LIGO/Virgo S190426c: Optical Wide-field Search with the Zwicky Transient Facility
  83. LIGO/Virgo S190425z: BOOTES-5/JGT observations of galaxies
  84. LIGO/Virgo S190425z: GRANDMA follow-up observations with Les Makes-T60, AZT-8 and Abastumani-T70
  85. LIGO/Virgo S190426c: SAO optical observation
  86. LIGO/Virgo S190425z: Further MMT Follow-Up Observations
  87. LIGO/Virgo S190425z: COATLI Observations of Galaxies
  88. LIGO/Virgo S190426c Global MASTER-Net observations report
  89. LIGO/Virgo S190425z: YAHPT Optical Observation
  90. LIGO/Virgo S190425z: Las Cumbres Observatory Galaxy Targeted Counterpart Search
  91. LIGO/Virgo S190425z: KMTNet Observation
  92. LIGO/Virgo S190425z: GRAWITA TNG observations of ZTF19aarzaod
  93. LIGO/Virgo S190425z: Las Cumbres Observatory Galaxy Targeted Counterpart Search
  94. LIGO/Virgo S190425z: ZTF19aarykkb Imaging from Las Cumbres Observatory
  95. LIGO/Virgo S190425z: J-GEM optical follow-up observations with Subaru/FOCAS
  96. LIGO/Virgo S190425z: Candidates from the Zwicky Transient Facility
  97. LIGO/Virgo S190408an: Gaia Photometric Alerts transient candidates
  98. LIGO/Virgo S190425z: MMT Follow-Up Observations
  99. LIGO/Virgo S190425z: Lick/KAIT Follow-Up Observations
  100. LIGO/Virgo S190425z: INTEGRAL SPI-ACS prompt observation

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