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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').
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"

4738 results found.

  1. GRB 160228A: GROND afterglow confirmation and X-shooter host candidate redshift
  2. GRB 160314A: ISON-Ussuriysk optical upper limit
  3. GRB 160314A: Weihai optical upper limit
  4. GRB 160314A: Swift detection of a burst
  5. GRB 160313A: MASTER-Net optical observations
  6. GRB 160313A: RATIR Optical and NIR Observations
  7. GRB 160310A: MASTER-Kislovods observations
  8. GRB 160310A: Further NOT observations
  9. GRB 160310A: RATIR Optical and NIR Observations
  10. GRB 160310A: NOT optical observations
  11. GRB 160310A: LCOGT-SAAO optical upper limits
  12. LIGO/Virgo G211117: HAWC follow-up of northern sky
  13. GRB 160303A: X-shooter spectroscopy
  14. GRB 160303A: JCMT SCUBA-2 sub-mm observation
  15. GRB160303A: further GROND observations
  16. GRB 160303A: Continued RATIR Optical and NIR Observations
  17. GRB 160303A: GROND Optical Detection
  18. GRB 160303A: VLT/FORS2 afterglow obervations
  19. GRB 160303A: McDonald 2.1m CQUEAN Detection
  20. GRB 160303A: RATIR Optical and NIR Afterglow Detection
  21. GRB 160303A: MITSuME Akeno optical upper limits
  22. GRB 160303A: LCOGT-FTN optical observations
  23. GRB 160303A: MITSuME Okayama upper limits
  24. GRB 160303A: ISON-NM early optical early limits
  25. GRB 160227A: McDonald 0.8m Detection
  26. GRB 160227A: MASTER prompt OT Detection and LC
  27. GRB 160227A: MASTER OT Detection
  28. Fermi GBM trigger 477460274/160218161 is not a GRB
  29. GRB 160223A: GROND optical/NIR afterglow
  30. LIGO/Virgo G211117: LOFAR follow-up
  31. GRB 160203A: MITSuME Akeno optical upper limits
  32. GRB 160203A: TSHAO optical observations
  33. GRB 160203A: Skynet PROMPT-CTIO observations of the optical afterglow
  34. The bright GRB160203A: X-shooter spectroscopy and redshift
  35. GRB 160203A: LCOGT-Cerro Tololo optical afterglow confirmation
  36. GRB 160203A: GROND Afterglow Candidate
  37. GRB 160131A: RATIR Optical Observations
  38. GRB 160131A: LCOGT-FTN optical afterglow observations
  39. GRB 160127A: VLA Detection
  40. GRB 160127A: Swift/UVOT Detection
  41. GRB 160127A: Swift detection of a burst with an optical counterpart
  42. GRB160119A: BOOTES-2/TELMA Early Upper Limits
  43. LIGO/Virgo G184098: MASTER final result
  44. GRB 160117B: Early iTelescope observation
  45. GRB 160119A: Swift detection of a burst
  46. GRB 160117B: VLT/X-shooter spectroscopy
  47. LIGO/Virgo G211117: Preliminary VLA observation summary of PS15dpn
  48. IPN Triangulation of GRB 160113A
  49. LIGO/Virgo G211117: Further Swift-XRT sources
  50. LIGO/Virgo G211117: Swift observations of PS15dpn
  51. LIGO/Virgo G211117: VISTA imaging
  52. GRB 160104A: Continued MITSuME Akeno Optical Observation
  53. LIGO/Virgo G211117: Subaru Hyper Suprime-Cam follow-up observation
  54. GRB 160107A: MAXI/GSC detection
  55. IPN Triangulation of GRB 151225A (short/hard)
  56. LIGO/Virgo G211117: Further Swift-XRT sources
  57. LIGO/Virgo G211117: Liverpool Telescope classification of EM candidates
  58. LIGO/Virgo G211117: Summary of Pan-STARRS transients
  59. GRB 160104B: MAXI/GSC detection
  60. LIGO/Virgo G211117: LOFAR follow-up
  61. LIGO/Virgo G211117: PESSTO classification of Pan-STARRS transients
  62. LIGO/Virgo G211117: CSS/CRTS observations on 29/30 Dec 2015 UT
  63. GRB 160102A: MAXI/GSC detection
  64. LIGO/Virgo G211117: 44 transients from Pan-STARRS data during 2015-12-28/30
  65. LIGO/Virgo G211117: MAXI/GSC observations
  66. LIGO/Virgo G211117: LBT Follow-up of iPTF15fen
  67. LIGO/Virgo G211117: MAGIC very-high energy gamma-ray observations
  68. LIGO/Virgo G211117: SkyMapper observations and transient candidate
  69. LIGO/Virgo G211117: Optical Observations with Kiso Schmidt telescope and KWFC
  70. LIGO/Virgo G211117: List of near-term future observation regions by Project Mini-GWAC of SVOM
  71. LIGO/Virgo G211117: iPTF Optical Transient Candidates
  72. LIGO/Virgo G211117: La Silla - QUEST observations 2015 Dec 28, 29
  73. LIGO/Virgo G211117: Further Swift-XRT sources
  74. GRB 151228A: T60 observations
  75. LIGO/Virgo G211117: Optical NIR observation with Kanata telescope
  76. LIGO/Virgo G211117: Optical follow-up with Kanata telescope
  77. LIGO/Virgo G211117: MASTER Observations and Inspection + OT
  78. LIGO/Virgo G211117: INTEGRAL was inactive at the time of the event
  79. GRB 151228A: Fermi GBM observation
  80. LIGO/Virgo G211117: INAF VST-ESO PARANAL observations
  81. LIGO/Virgo G211117: Further Swift-XRT sources
  82. GRB 151228A: Swift detection of a short burst
  83. LIGO/Virgo G211117: Identification of a GW CBC Candidate
  84. GRB 151212A iTelescope observation
  85. V404Cyg Swift Trigger 668097:
  86. GRB 151216A: MAXI/GSC detection
  87. GRB151215A: Early optical light curve from pt5m, La Palma
  88. GRB 151215A: MASTER early OT detection and light curve
  89. GRB 151215A: Swift detection of a burst
  90. GRB 151212A: GROND Optical Afterglow Candidate
  91. GRB 151212A: Swift-XRT afterglow detection
  92. GRB 151212A: MAXI/GSC detection
  93. GRB 151210A: GROND Afterglow Confirmation
  94. GRB 151210A: Optical afterglow candidate from LCOGT-Cerro Tololo
  95. GRB 151210A: Swift detection of a burst
  96. GRB 151205C: Optical follow-up observations at Kiso
  97. Swift detection of 4U 1850-03
  98. GRB 130831A: MASTER early OT detection and LC
  99. Fermi GBM trigger 470375959/151128166 is not a GRB
  100. GRB 151118A iTelescope observation

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