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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"

11848 results found.

  1. IceCube-191001A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  2. IceCube-191001A - IceCube observation of a high-energy neutrino candidate event
  3. LIGO/Virgo S190930s: No counterpart candidates in KAIT observations
  4. GRB 191001A: DDOTI Optical Counterpart Candidate
  5. IceCube Alert 191001.84: Global MASTER-Net observations report
  6. LIGO/Virgo S190814bv: VLA 6 GHz observations of 75 galaxies in the 90% localization region
  7. GRB 191001B: Swift detection of a burst
  8. LIGO/Virgo S190930t: No counterpart candidates in Fermi-LAT observations
  9. LIGO/Virgo S190930s: No counterpart candidates in Fermi-LAT observations
  10. LIGO/Virgo S190930s: Upper limits from CALET observations.
  11. LIGO/Virgo S190930t: Coverage and upper limits from MAXI/GSC observations
  12. LIGO/Virgo S190930t: No counterpart candidates in HAWC observations
  13. LIGO/Virgo S190930s: Coverage and upper limits from MAXI/GSC observations
  14. Fermi trigger No 591532362: Global MASTER-Net observations report
  15. Konus-Wind observation of GRB 190928A
  16. Fermi trigger No 591391412: Global MASTER-Net observations report
  17. GRB 190928A: AGILE/MCAL detection of a burst
  18. GRB 190926A: Swift-XRT refined Analysis
  19. LIGO/Virgo S190923y: No significant candidates in TAROT-GRANDMA observations
  20. LIGO/Virgo S190924h: No counterpart candidates in Fermi-LAT observations
  21. Fermi-LAT Gamma-ray Observations of IceCube-190922B
  22. LIGO/Virgo S190924h: Coverage and upper limits from MAXI/GSC observations
  23. LIGO/Virgo S190923y: No counterpart candidates in Fermi-LAT observations
  24. Fermi-LAT Gamma-ray Observations of IceCube-190922A
  25. LIGO/Virgo S190923y: Coverage and upper limits from MAXI/GSC observations
  26. LIGO/Virgo S190923y: No counterpart candidates in HAWC observations
  27. IceCube Alert 190922.96: Global MASTER-Net observations report
  28. IceCube-190922A - IceCube observation of a high-energy neutrino candidate event
  29. Baksan Neutrino Observatory Alert 190920.65: Global MASTER-Net observations report
  30. GRB 190919B: LCO Optical Afterglow Detection
  31. GRB 190919B: FRAM-Auger optical detection
  32. GRB 190919B: Swift-XRT observations
  33. GRB 190919B: A long GRB detected by INTEGRAL
  34. Integral GRB190919.99: Global MASTER-Net observations report
  35. Fermi trigger No 590621700: Global MASTER-Net observations report
  36. GRB 190919A: Fermi GBM Final Real-time Localization
  37. LIGO/Virgo S190915ak: No significant candidates in TAROT-GRANDMA observations
  38. LIGO/Virgo S190910h: No significant candidates in TAROT-GRANDMA observations
  39. LIGO/Virgo S190915ak: No counterpart candidates in Fermi-LAT observations
  40. LIGO/Virgo S190915ak: Coverage and upper limits from MAXI/GSC observations
  41. LIGO/Virgo S190915ak: Global MASTER-Net observations report
  42. LIGO/Virgo S190910d : No significant candidates in TAROT-GRANDMA observations
  43. Fermi trigger No 590038994: Global MASTER-Net observations report
  44. LIGO/Virgo S190910h: No counterpart candidates in Fermi-LAT observations
  45. LIGO/Virgo S190910h: Gaia Photometric Alerts transient candidates
  46. LIGO/Virgo S190910d and S190910h: No counterpart candidates in KAIT observations
  47. LIGO/Virgo S190910d: AT2019pvu, AT2019pvv, AT2019pvz and AT2019pwa 10.4m GTC spectroscopy
  48. LIGO/Virgo S190910d: Liverpool Telescope spectroscopy of ZTF19abyfazm
  49. LIGO/Virgo S190910d: AstroSat CZTI upper limits
  50. LIGO/Virgo S190910d: No counterpart candidates in Fermi-LAT observations
  51. LIGO/Virgo S190910h: No counterpart candidates in HAWC observations
  52. LIGO/Virgo S190910h Global MASTER-Net observations report
  53. LIGO/Virgo S190910h: Coverage and upper limits from MAXI/GSC observations
  54. LIGO/Virgo S190910d: Coverage and upper limits from MAXI/GSC observations
  55. LIGO/Virgo S190910d: No counterpart candidates in HAWC observations
  56. LIGO/Virgo S190901ap : No significant candidates found in GRANDMA citizen science observations
  57. ZTF19abvizsw: AbAO and CrAO photometry
  58. LIGO/Virgo S190814bv: GRAWITA VST-ESO PARANAL observations and independent transient candidates discovery.
  59. LIGO/Virgo S190901ap : No significant candidates in TAROT-GRANDMA
  60. LIGO/Virgo S190901ap: No counterpart candidates in KAIT observations
  61. Konus-Wind observation of GRB 190829A
  62. Swift XRT Detection of X-ray Emission from ZTF19abvizsw
  63. LIGO/Virgo S190901ap: GOTO optical coverage and detection of AT2019pjv
  64. LIGO/Virgo S190901ap: GTC follow-up spectroscopic observations of ZTF19abvizsw
  65. LIGO/Virgo S190901ap : GRAWITA photometric observation of candidate ZTFabvizsw and GCN 25618 revision
  66. LIGO/Virgo S190901ap: no counterpart candidate in the SVOM/GWAC observations
  67. Liverpool Telescope observations of ZTF19abvizsw, a candidate untriggered GRB afterglow
  68. LIGO/Virgo S190901ap: Upper limits from AGILE-GRID observations
  69. LIGO/Virgo S190828l: no counterpart candidate in the SVOM/GWAC observations
  70. LIGO/Virgo S190828j: no counterpart candidate in the SVOM/GWAC observations
  71. LIGO/Virgo S190901ap: No counterpart candidates in Fermi-LAT observations
  72. LIGO/Virgo S190901ap: Coverage and upper limits from MAXI/GSC observations
  73. LIGO/Virgo S190901ap: No counterpart candidates in HAWC observations
  74. Fermi trigger No 589060361 Global MASTER-Net observations report
  75. GRB 190829A: Keck LRIS spectroscopy of the optical afterglow
  76. LIGO/Virgo S190828j : No significant candidates in TAROT-GRANDMA observations
  77. LIGO/Virgo S190828l: No significant candidates in TAROT-GRANDMA observations
  78. GRB 190829A: Follow up VLA and VLBI radio observations urged
  79. GRB 190829A, Swift-BAT refined analysis
  80. GRB 190829A: Fermi GBM detection
  81. GRB 190829A: Fermi-LAT Upper Limits
  82. GRB 190829A:: Global MASTER-net optical clear and polarization observations scheduler and some spiculations
  83. GRB 190829A: Swift-XRT refined Analysis
  84. GRB 190830B: Fermi GBM Final Real-time Localization
  85. LIGO/Virgo S190828l: No counterpart candidates in KAIT observations
  86. GRB 190829A:: MASTER-net bright and decay OT detection
  87. GRB 190829A: Dabancheng-0.5m optical afterglow detection
  88. Fermi trigger No 588801358 Global MASTER-Net observations report
  89. GRB 190828B: Swift-XRT refined Analysis
  90. LIGO/Virgo S190814bv: VLA observation of ASKAP J005547-270433/AT2019osy
  91. LIGO/Virgo S190828l: No counterpart candidates in Fermi-LAT observations
  92. LIGO/Virgo S190828j: No counterpart candidates in KAIT observations
  93. LIGO/Virgo S190828j: No counterpart candidates in Fermi-LAT observations
  94. GRB 190828D: A long GRB detected by INTEGRAL
  95. Integral GRB190828.78 Global MASTER-Net observations report
  96. GRB 190828B: Swift detection of a burst
  97. LIGO/Virgo S190828l: Coverage and upper limits from MAXI/GSC observations
  98. LIGO/Virgo S190828j: Coverage and upper limits from MAXI/GSC observations
  99. LIGO/Virgo S190828l: No counterpart candidates in HAWC observations
  100. LIGO/Virgo S190828j: No counterpart candidates in HAWC observations

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