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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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

16146 results found.

  1. GRB 150211A: ROTSE-III Upper Optical Limit
  2. GRB 150212A: RATIR Optical and NIR Observations
  3. GRB 150212A: Khureltogot optical upper limit
  4. GRB 150212A: Skynet DSO14/GORT observations
  5. GRB 150212A: MASTER optical observations
  6. GRB150212A: P60 Afterglow Candidate
  7. GRB 150211A iTelescope observation
  8. GRB 150211A: Swift/UVOT Upper Limits
  9. GRB 150211A: KAIT Optical Upper Limit
  10. GRB 150211A: Mondy optical upper limit
  11. GRB 150211A: RATIR Optical and NIR Observations
  12. GRB 150211A: MASTER early optical observations
  13. GRB 150101B/ Swift J123205.1-105602: Second epoch Chandra observations
  14. GRB 150203A iTelescope observation
  15. GRB 140206B: Continued iPTF Observations
  16. GRB 150206A: GROND afterglow observations
  17. GRB 150206B: Fermi GBM detection
  18. Trigger 630047: Swift detection of 1RXS J180408.9-342058
  19. GRB 150206B: iPTF Optical Observations
  20. GRB 150206A: Swift detection of a burst with an optical afterglow
  21. GRB 150204A: Swift/UVOT Upper Limits
  22. GRB 150203A: RAPTOR Limits Beginning at the Gamma-Ray Emitting Interval
  23. GRB 150203A: Swift/UVOT Upper Limits
  24. GRB 150203A: ISON-NM early optical limit
  25. GRB 150203A: MITSuME Okayama upper limits
  26. GRB 150202A: Swift/UVOT Upper Limits
  27. GRB 150203A: REM optical and NIR observations
  28. GRB 150203A: TAROT La Silla observatory optical observations
  29. GRB 150203A: RATIR Optical and NIR Observations
  30. GRB 150203A: KAIT Optical Upper Limit
  31. GRB 150201A: Swift/UVOT Upper Limits
  32. GRB 150120B: Khureltogot optical observations
  33. GRB 150120A: Gemini-N imaging and host redshift
  34. GRB 150123A: Swift/UVOT observations
  35. GRB 150123A: Swift-XRT observations
  36. GRB 150120B: Mondy optical observations
  37. GRB 150120B: RATIR Optical and NIR Observations
  38. GRB 150120A: ISON-NM early optical limit
  39. GRB 150120B: FTN early optical light curve
  40. GRB150120B: Xinglong TNT optical observation
  41. GRB 150120B: Swift/UVOT Upper Limits
  42. GRB 150120B, Optical observations
  43. GRB 150120B: Additional P60 observations
  44. GRB 150101B: Confirmation of a fading optical counterpart
  45. GRB 150120A: KAIT Optical Upper Limit
  46. GRB 150120B: MITSuME Okayama upper limits
  47. GRB 150101B/Swift J123205.1-105602: TNG NIR follow-up
  48. GRB 150120A: Swift/UVOT Upper Limits
  49. GRB 150101B/Swift J123205.1-105602, deep VLT observations
  50. GRB 150120B: FTN optical afterglow confirmation
  51. GRB 150120B: P60 optical afterglow
  52. GRB 150120A: Gemini-North optical imaging
  53. GRB 150120A: P60 optical observations
  54. GRB 150101B/Swift J123205.1-105602: continued WSRT radio and VLT optical observations
  55. GRB 150110B: Khureltogot optical upper limit
  56. The Swift Detection of a Large Flare from the RS CVn Binary SZ Psc
  57. GRB 150110C: Swift/UVOT Upper Limits
  58. GRB 150110A: MASTER inspection
  59. GRB 150110B: Swift/UVOT Upper Limits
  60. GRB 150101B/Swift J123205.1-105602: Chandra observations
  61. GRB 150101B / Swift J123205.1-105602: 9.8 GHz VLA observations
  62. GRB 150101B/Swift J123205.1-105602: WSRT radio observation
  63. GRB 150101B / Swift J123205.1-105602: X-ray counterpart is likely an AGN
  64. GRB 150101B/Swift J123205.1-105602: VLT observations and redshift
  65. GRB 150103A: MASTER optical observations
  66. GRB 150101B: potential host galaxy redshift by GTC
  67. GRB 150103A: Swift/UVOT Upper Limits
  68. GRB 150103A: Zadko observatory - Gingin optical observations
  69. Swift J123205.1-105602: Magellan candidate afterglow
  70. Swift J123205.1-105602: XRT and UVOT observations of soft short burst source
  71. GRB 150101A: Swift/UVOT Upper Limits
  72. GRB 141229A: Deep MASTER inspection
  73. Swift-XRT and UVOT follow-up of iPTF14jko (GRB 141230A)
  74. GRB 141230A: Nanshan optical obsrvations
  75. GRB 141230A: iPTF Optical Observations and Candidate Afterglow iPTF14jko
  76. GRB 141229A: 1.23m CAHA optical observations
  77. GRB 141229A: Nanshan optical upper limit
  78. GRB 141225A: MITSuME Okayama upper limits
  79. GRB 141225A: TAROT Calern observatory optical observations
  80. GRB 141225A: Swift/UVOT refined analysis
  81. GRB 141225A: Fermi GBM detection
  82. GRB 141225A: Nanshan very early optical observations
  83. GRB 141225A: Optical aftergow confirmation
  84. GRB 141225A: LT optical candidate
  85. GRB 141225A: 1.23m CAHA optical observations
  86. GRB 141221A: Keck spectroscopy
  87. GRB 141221A: TAROT La Silla observatory optical observations
  88. Swift XRT and UVOT observations of GRB141222A
  89. GRB 141222A: First MASTER-SAAO optical observation
  90. GRB 141221A: MITSuME Akeno upper limits
  91. GRB 141221A: Continued Skynet PROMPT-CTIO observations
  92. GRB 141215A: further Swift-XRT observations and afterglow detection
  93. GRB 141220A: MITSuME Akeno upper limits
  94. GRB141221A: GROND Afterglow Detection
  95. GRB 141221A: Skynet PROMPT-CTIO observations of the optical afterglow
  96. GRB 141221A: LCOGT-McDonald optical afterglow observations
  97. GRB141221A: REM afterglow
  98. GRB 141221A: Swift detection of a burst with an optical counterpart
  99. GRB 141220A: MITSuME Okayama upper limits
  100. GRB 141220A: Swift/UVOT Detection

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