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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"

28118 results found.

  1. GRB 201221D: SMA submm observation
  2. GRB 201221D: LCOGT upper limits
  3. GRB 201221D: Swift-BAT refined analysis
  4. Swift Trigger 1014012 (possible GRB 201221C) is likely not an astrophysical event
  5. GRB 201216A - further Swift-XRT observations
  6. Fermi-LAT Gamma-ray Observations of IceCube-201222A
  7. Fermi-LAT Gamma-ray Observations of IceCube-201221A
  8. GRB 201221D: Archival PS1 Imaging of the Putative Host Galaxy
  9. Short GRB201221D: High Redshift from OSIRIS/GTC
  10. IceCube-201222A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  11. Konus-Wind detection of GRB 201221D (short)
  12. GRB 201221D: Swift/UVOT Upper Limits
  13. GRB 201221D: Lowell Discovery Telescope afterglow observations
  14. GRB 201222B: BALROG localization (Fermi Trigger / GRB 201222461)
  15. GRB 201221D: FRAM-ORM optical limit
  16. GRB 201221D: Enhanced Swift-XRT position
  17. GRB 201221D: Nanshan/NEXT early optical upper limit
  18. GRB 201221D: candidate optical counterpart from the NOT
  19. GRB 201221A: Swift-BAT refined analysis
  20. GRB 201221D: Swift detection of a bright short burst
  21. correction to GCN 29110 - Fermi GBM Sub-Threshold Detection of GRB 201221A
  22. Fermi GBM Sub-Threshold Detection of GRB 201221A
  23. GRB 201221A: Swift/UVOT Upper Limits
  24. GRB 201221A: Swift-XRT refined Analysis
  25. Swift Trigger 1014012: possible GRB 201221C
  26. GRB 201221A: Enhanced Swift-XRT position
  27. IceCube-201221A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  28. GRB 201221A: VLT/X-shooter afterglow discovery and spectroscopic redshift z = 5.7
  29. GRB 201221A: Swift detection of a burst
  30. GRB 201209A: Mondy optical observations, afterglow confirmation
  31. GRB 201214A: TSHAO optical upper limit
  32. GRB 201214A: Swift-XRT afterglow detection
  33. GRB 201214A: 1.3m DFOT, optical upper limits
  34. IPN triangulation of GRB 201218A
  35. GRB201216C: No significant detection in HAWC
  36. GRB 201216C: Liverpool Telescope First Hour Observations
  37. GRB 201218A: BALROG localization (Fermi Trigger 629957660 / GRB 201218177)
  38. IceCube-201209A : MAXI/GSC upper limit
  39. GRB 201216C: Swift-BAT refined analysis
  40. GRB 201216C: Fermi-LAT upper limit
  41. GRB 201216C: Fermi GBM detection
  42. GRB 201216A: Fermi GBM detection
  43. GRB 201216C: Swift/UVOT Upper Limits
  44. GRB 201216A: Swift-XRT observations
  45. GRB 201216C: Enhanced Swift-XRT position
  46. GRB 201216C: VLT afterglow candidate discovery
  47. GRB 201216C: Swift-XRT observations
  48. GRB 201216A: Swift/BAT-GUANO detection and arcminute localization
  49. GRB 201214B: MITSuME Akeno optical upper limits
  50. Chandra observations of GW170817 at ~3.3 years since merger (Full report)
  51. GRB 201214B: Lowell Discovery Telescope optical observations
  52. GRB 201214B: Swift-XRT observations
  53. GRB 201209A: Insight-HXMT/HE detection
  54. IceCube-201209A: Upper limits from Insight-HXMT/HE observations
  55. GRB 201214A: Swift-XRT observations
  56. GRB 201215A: BALROG localization (Fermi Trigger 629706213 / GRB 201215266)
  57. IceCube-201209: No significant detection in HAWC
  58. Potential X-ray KN afterglow from Chandra observations of GW170817 ~3.3 years since merger (3 Epochs of 4)
  59. Long-lasting X-ray emission from GW170817 detected by Chandra
  60. GRB 201214A: A long GRB detected by INTEGRAL
  61. Integral GRB201214.26: Global MASTER-Net observations report
  62. GRB 201015A: optical observations and supernova identification
  63. GRB 201203A: Zeiss-1000 (Koshka observatory) optical upper limit
  64. GRB 201203A: 1.3m DFOT, optical upper limits
  65. GRB 200826A: GMOS-N detected source magnitude (Correction)
  66. GRB 201015A: 5-GHz radio afterglow detection with the EVN
  67. GRB 201209A: Swift/UVOT Upper Limits
  68. Fermi-LAT Gamma-ray Observations of IceCube-201209A
  69. IceCube-201209A: No neutrino counterpart candidates in ANTARES search
  70. GRB 201209A: Swift-BAT refined analysis
  71. Chandra observations of GW170817 at ~3.3 years since merger (Observation 1 of 4)
  72. GRB 201208A: Swift-XRT afterglow detection
  73. GRB 201208A: Fermi GBM observation
  74. IceCube-201209A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  75. GRB 201208A: LCO observations
  76. GRB 201209A: Swift-XRT refined Analysis
  77. GRB 201209A: Xinglong-2.16m likely optical afterglow detection
  78. GRB 201209A: Enhanced Swift-XRT position
  79. IceCube-201130A: Optical and NIR Imaging Follow-up by Kanata Telescope
  80. GRB 201209A: Swift detection of a burst
  81. GRB 201207A: AstroSat CZTI detection
  82. GRB 201203A: Swift-BAT refined analysis
  83. Swift follow-up observations of the flat spectrum radio quasar PMN J0206-1150 in the error region of IceCube-201130A
  84. GRB 201203A: GROWTH-India Telescope optical upper limit.
  85. GRB 201203A: MITSuME Okayama optical upper limits
  86. GRB 201203A: Swift-XRT afterglow detection
  87. GRB 201203A: DDOTI Observations
  88. GRB 201203A: Swift detection of a burst
  89. IceCube-201130A: No significant detection in HAWC
  90. IceCube-201130A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  91. GRB 201128B: Swift-XRT observations
  92. Swift observations of the Fermi-LAT source 4FGL J0206.4-1151 in the error region of IceCube-201130A
  93. Fermi-LAT Gamma-ray Observations of IceCube-201130A
  94. GRB 201201A: DDOTI Observations
  95. Swift-XRT observations of IceCube 201130A
  96. GRB 201201A: Fermi GBM Final Real-time Localization
  97. GRB 201128B: Swift/BAT-GUANO detection and arcminute localization
  98. GRB 201128A: Swift/UVOT Upper Limits
  99. GRB 201130A: DDOTI Observations
  100. Baksan Neutrino Observatory Alert 201128.90: Global MASTER-Net observations report

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