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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"

4744 results found.

  1. GRB 160314A: Continued RATIR Optical and NIR Observations
  2. GRB 160313A: Mondy optical upper limit
  3. GRB 160314A: GROND optical/NIR observations
  4. GRB 160314A: ISON-Ussuriysk optical upper limit, updated photometry and correction of GCN 19184
  5. GRB 160314A: RATIR Optical and NIR Observations
  6. GRB 160314A: Mondy optical observations
  7. GRB 160228A: GROND afterglow confirmation and X-shooter host candidate redshift
  8. GRB 160314A: ISON-Ussuriysk optical upper limit
  9. GRB 160314A: Weihai optical upper limit
  10. GRB 160314A: Swift detection of a burst
  11. GRB 160313A: MASTER-Net optical observations
  12. GRB 160313A: RATIR Optical and NIR Observations
  13. GRB 160310A: MASTER-Kislovods observations
  14. GRB 160310A: Further NOT observations
  15. GRB 160310A: RATIR Optical and NIR Observations
  16. GRB 160310A: NOT optical observations
  17. GRB 160310A: LCOGT-SAAO optical upper limits
  18. LIGO/Virgo G211117: HAWC follow-up of northern sky
  19. GRB 160303A: X-shooter spectroscopy
  20. GRB 160303A: JCMT SCUBA-2 sub-mm observation
  21. GRB160303A: further GROND observations
  22. GRB 160303A: Continued RATIR Optical and NIR Observations
  23. GRB 160303A: GROND Optical Detection
  24. GRB 160303A: VLT/FORS2 afterglow obervations
  25. GRB 160303A: McDonald 2.1m CQUEAN Detection
  26. GRB 160303A: RATIR Optical and NIR Afterglow Detection
  27. GRB 160303A: MITSuME Akeno optical upper limits
  28. GRB 160303A: LCOGT-FTN optical observations
  29. GRB 160303A: MITSuME Okayama upper limits
  30. GRB 160303A: ISON-NM early optical early limits
  31. GRB 160227A: McDonald 0.8m Detection
  32. GRB 160227A: MASTER prompt OT Detection and LC
  33. GRB 160227A: MASTER OT Detection
  34. Fermi GBM trigger 477460274/160218161 is not a GRB
  35. GRB 160223A: GROND optical/NIR afterglow
  36. LIGO/Virgo G211117: LOFAR follow-up
  37. GRB 160203A: MITSuME Akeno optical upper limits
  38. GRB 160203A: TSHAO optical observations
  39. GRB 160203A: Skynet PROMPT-CTIO observations of the optical afterglow
  40. The bright GRB160203A: X-shooter spectroscopy and redshift
  41. GRB 160203A: LCOGT-Cerro Tololo optical afterglow confirmation
  42. GRB 160203A: GROND Afterglow Candidate
  43. GRB 160131A: RATIR Optical Observations
  44. GRB 160131A: LCOGT-FTN optical afterglow observations
  45. GRB 160127A: VLA Detection
  46. GRB 160127A: Swift/UVOT Detection
  47. GRB 160127A: Swift detection of a burst with an optical counterpart
  48. GRB160119A: BOOTES-2/TELMA Early Upper Limits
  49. LIGO/Virgo G184098: MASTER final result
  50. GRB 160117B: Early iTelescope observation
  51. GRB 160119A: Swift detection of a burst
  52. GRB 160117B: VLT/X-shooter spectroscopy
  53. LIGO/Virgo G211117: Preliminary VLA observation summary of PS15dpn
  54. IPN Triangulation of GRB 160113A
  55. LIGO/Virgo G211117: Further Swift-XRT sources
  56. LIGO/Virgo G211117: Swift observations of PS15dpn
  57. LIGO/Virgo G211117: VISTA imaging
  58. GRB 160104A: Continued MITSuME Akeno Optical Observation
  59. LIGO/Virgo G211117: Subaru Hyper Suprime-Cam follow-up observation
  60. GRB 160107A: MAXI/GSC detection
  61. IPN Triangulation of GRB 151225A (short/hard)
  62. LIGO/Virgo G211117: Further Swift-XRT sources
  63. LIGO/Virgo G211117: Liverpool Telescope classification of EM candidates
  64. LIGO/Virgo G211117: Summary of Pan-STARRS transients
  65. GRB 160104B: MAXI/GSC detection
  66. LIGO/Virgo G211117: LOFAR follow-up
  67. LIGO/Virgo G211117: PESSTO classification of Pan-STARRS transients
  68. LIGO/Virgo G211117: CSS/CRTS observations on 29/30 Dec 2015 UT
  69. GRB 160102A: MAXI/GSC detection
  70. LIGO/Virgo G211117: 44 transients from Pan-STARRS data during 2015-12-28/30
  71. LIGO/Virgo G211117: MAXI/GSC observations
  72. LIGO/Virgo G211117: LBT Follow-up of iPTF15fen
  73. LIGO/Virgo G211117: MAGIC very-high energy gamma-ray observations
  74. LIGO/Virgo G211117: SkyMapper observations and transient candidate
  75. LIGO/Virgo G211117: Optical Observations with Kiso Schmidt telescope and KWFC
  76. LIGO/Virgo G211117: List of near-term future observation regions by Project Mini-GWAC of SVOM
  77. LIGO/Virgo G211117: iPTF Optical Transient Candidates
  78. LIGO/Virgo G211117: La Silla - QUEST observations 2015 Dec 28, 29
  79. LIGO/Virgo G211117: Further Swift-XRT sources
  80. GRB 151228A: T60 observations
  81. LIGO/Virgo G211117: Optical NIR observation with Kanata telescope
  82. LIGO/Virgo G211117: Optical follow-up with Kanata telescope
  83. LIGO/Virgo G211117: MASTER Observations and Inspection + OT
  84. LIGO/Virgo G211117: INTEGRAL was inactive at the time of the event
  85. GRB 151228A: Fermi GBM observation
  86. LIGO/Virgo G211117: INAF VST-ESO PARANAL observations
  87. LIGO/Virgo G211117: Further Swift-XRT sources
  88. GRB 151228A: Swift detection of a short burst
  89. LIGO/Virgo G211117: Identification of a GW CBC Candidate
  90. GRB 151212A iTelescope observation
  91. V404Cyg Swift Trigger 668097:
  92. GRB 151216A: MAXI/GSC detection
  93. GRB151215A: Early optical light curve from pt5m, La Palma
  94. GRB 151215A: MASTER early OT detection and light curve
  95. GRB 151215A: Swift detection of a burst
  96. GRB 151212A: GROND Optical Afterglow Candidate
  97. GRB 151212A: Swift-XRT afterglow detection
  98. GRB 151212A: MAXI/GSC detection
  99. GRB 151210A: GROND Afterglow Confirmation
  100. GRB 151210A: Optical afterglow candidate from LCOGT-Cerro Tololo

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