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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').
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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"

41750 results found.

  1. LIGO/Virgo G194575: MAXI/GSC further analysis
  2. GRB 150910A: CrAO optical observations
  3. GRB 151027A: the missing GeV component
  4. GRB 151029A: FRAM optical afterglow detection
  5. LIGO/Virgo G194575: LT Spectroscopy of iPTF-15dmk
  6. GRB 151027A: Correction to GCN 18519
  7. GRB 151031A: MITSuME Akeno optical upper limits
  8. GRB 151031A: GROND observation
  9. LIGO/Virgo G194575: LT Spectroscopy of iPTF candidates
  10. GRB 151027B: ATCA radio detection
  11. GRB 151031A
  12. GRB 151031A: Swift/UVOT Detection
  13. GRB 151030A: Fermi GBM observation
  14. GRB 151031A: Swift-XRT refined Analysis
  15. GRB 151027B: RATIR Late-Time Upper Limits
  16. GRB 151031A: Swift-BAT refined analysis
  17. GRB 151031A: VLT/X-shooter optical counterpart and redshift
  18. GRB 151031A: Swift detection of a burst
  19. GRB 151027A: Continued P60 Monitoring
  20. LIGO/Virgo G194575: INAF-TNG follow-up of iPTF15dkm and iPTF15dlj
  21. Correction to the Trigger Time for Swift GRB 151029A
  22. GRB 151029A: MITSuME Ishigakijima upper limits
  23. GRB 151027A: Optical counterpart detection
  24. GRB 151029A: Swift-XRT refined Analysis
  25. GRB 151029A: Swift/UVOT Detection
  26. GRB 151029A: LCOGT-FTS afterglow observations
  27. GRB 151027B: Swift UVOT detection
  28. LIGO/Virgo G194575: VLA follow-up
  29. GRB 151029A: Swift-BAT refined analysis
  30. GRB 151027A: MAXI/GSC detection
  31. GRB 151029A VLT/X-shooter redshift
  32. GRB 151029A: GROND afterglow observations
  33. GRB 151029A: Swift detection of a burst with an optical counterpart
  34. GRB 151027A: SAO RAS optical observations
  35. GRB 151027B: LCOGT FTN afterglow observations
  36. GRB 151027A: NOT optical and NIR observations
  37. GRB 151027A: T100 observations
  38. GRB 151027B: Swift/UVOT Upper Limits
  39. Konus-Wind observation of GRB 151027A
  40. GRB 151027A : Xinglong TNT optical observation
  41. GRB 151027B: Swift-BAT refined analysis
  42. GRB 151027A: continued GMG observation
  43. GRB 151027B: RATIR Observations
  44. GRB 151027B: MASTER-NET early OT detection
  45. GRB 151027A: LCOGT-McDonald afterglow observations
  46. GRB 151027B: Swift-XRT refined Analysis
  47. GRB 151027A: VLA detection
  48. GRB 151027B: GROND Optical/NIR Afterglow Detection
  49. GRB 151027B: VLT/X-shooter redshift
  50. GRB 151027A: UVOT Observations
  51. GRB 151027B: NOT optical afterglow candidate
  52. LIGO/Virgo G194575 : RATIR Observation of La Silla - QUEST Candidate
  53. GRB 151027B: Swift detection of its 1000-th burst
  54. LIGO/Virgo G194575: iPTF Optical Transient Candidates
  55. GRB 151027A: Swift-BAT refined analysis
  56. GRB 151027A: Early RAPTOR Observations
  57. LIGO/Virgo G194575: MASTER Optical Inspection
  58. GRB 151027A: GMG observation
  59. GRB 151027A: Fermi GBM observation
  60. GRB 151027A: MITSuME Akeno Optical observation
  61. GRB 151027A: Swift-XRT refined Analysis
  62. LIGO/Virgo G194575: Swift observations of LSQ15bjb
  63. LIGO/Virgo G194575: INAF-TNG spectra of LSQ15bjb
  64. GRB 151027A: Keck/HIRES redshift
  65. LIGO/Virgo G194575: GROND multi-color observations
  66. GRB 151027A: Weihai optical observations
  67. LIGO/Virgo G194575: further Pan-STARRS observations of the RA=1hr localisation region
  68. Tentative redshift for GRB 151027A from Swift-XRT data
  69. GRB 151027A: P60 afterglow confirmation and rebrightening
  70. GRB 151027A : ISON-NM early optical detection
  71. GRB 151027A: KAIT optical afterglow confirmation
  72. GRB 151027A: Swift detection of a burst with a bright optical afterglow
  73. LIGO/Virgo G194575: INAF-TNG follow-up of LSQ15bjb
  74. GRB 151006A: CALET Gamma-Ray Burst Monitor detection
  75. LIGO/Virgo G184098: VLA follow-up of iPTF15cyk
  76. LIGO/Virgo G194575 : La Silla - QUEST followup
  77. GRB 151021A: Skynet PROMPT-CTIO/DSO17 observations of the optical afterglow
  78. LIGO/Virgo G194575: Near-infrared follow-up with OAO-WFC
  79. LIGO/Virgo G194575: Kanata/J-GEM optical follow-up
  80. GRB 151023A: Swift-BAT refined analysis
  81. LIGO/Virgo G194575: Pi of the Sky observations
  82. LIGO/Virgo G194575: MAXI/GSC observations
  83. LIGO/Virgo G194575: Swift observations
  84. GRB 151022A: OSN optical upper limit
  85. GRB 151023A: RATIR Observations
  86. GRB 151023A: Swift-XRT refined Analysis
  87. GRB 151023A: Swift/UVOT Upper Limits
  88. GRB 151023A
  89. LIGO/Virgo G194575: CQUEAN/LOAO observations
  90. Possible Fermi-LAT Gamma-ray counterpart for LIGO/Virgo G194575
  91. LIGO/Virgo G194575: LOFAR follow-up
  92. GRB 151022A: Swift/UVOT Upper Limits
  93. LIGO/Virgo G194575: RATIR Observations of Nearby Galaxies in the 1sigma Error Region
  94. LIGO Virgo G194575: MWA Observations
  95. LIGO/Virgo G194575: INTEGRAL search of temporally coincident prompt hard X-ray emission
  96. LIGO/Virgo G194575: RATIR Observations of Nearby Galaxies in the 1sigma Error Region
  97. GRB 151022A: Swift-BAT refined analysis
  98. LIGO/Virgo G194575: more details on transients from Pan-STARRS in the RA=1hr localisation region
  99. GRB 151023A: Swift detection of a burst
  100. GRB 151022A: RATIR Upper Limits

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