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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"

16290 results found.

  1. GRB 151027A: Correction to GCN 18519
  2. GRB 151031A: MITSuME Akeno optical upper limits
  3. GRB 151027B: ATCA radio detection
  4. GRB 151031A
  5. GRB 151027B: RATIR Late-Time Upper Limits
  6. GRB 151031A: VLT/X-shooter optical counterpart and redshift
  7. GRB 151027A: optical follow-up observations
  8. GRB 151027A: Continued P60 Monitoring
  9. LIGO/Virgo G194575: INAF-TNG follow-up of iPTF15dkm and iPTF15dlj
  10. GRB 151029A: MITSuME Ishigakijima upper limits
  11. GRB 151027A: Optical counterpart detection
  12. GRB 151029A: LCOGT-FTS afterglow observations
  13. GRB 151027B: Swift UVOT detection
  14. GRB 151029A VLT/X-shooter redshift
  15. GRB 151029A: Swift detection of a burst with an optical counterpart
  16. GRB 151027A: SAO RAS optical observations
  17. GRB 151027B: LCOGT FTN afterglow observations
  18. GRB 151027A: NOT optical and NIR observations
  19. GRB 151027B: Swift/UVOT Upper Limits
  20. GRB 151027A : Xinglong TNT optical observation
  21. GRB 151027A: continued GMG observation
  22. GRB 151027B: MASTER-NET early OT detection
  23. GRB 151027A: LCOGT-McDonald afterglow observations
  24. GRB 151027A: VLA detection
  25. GRB 151027B: GROND Optical/NIR Afterglow Detection
  26. GRB 151027B: VLT/X-shooter redshift
  27. GRB 151027A: THO optical observations
  28. GRB 151027B: NOT optical afterglow candidate
  29. LIGO/Virgo G194575: iPTF Optical Transient Candidates
  30. GRB 151027A: Early RAPTOR Observations
  31. LIGO/Virgo G194575: MASTER Optical Inspection
  32. GRB 151027A: GMG observation
  33. GRB 151027A: MITSuME Akeno Optical observation
  34. LIGO/Virgo G194575: Swift observations of LSQ15bjb
  35. LIGO/Virgo G194575: INAF-TNG spectra of LSQ15bjb
  36. GRB 151027A: Keck/HIRES redshift
  37. LIGO/Virgo G194575: GROND multi-color observations
  38. GRB 151027A: Weihai optical observations
  39. GRB 151027A: P60 afterglow confirmation and rebrightening
  40. GRB 151027A : ISON-NM early optical detection
  41. GRB 151027A: KAIT optical afterglow confirmation
  42. GRB 151027A: Swift detection of a burst with a bright optical afterglow
  43. LIGO/Virgo G194575: ASKAP followup
  44. LIGO/Virgo G194575: INAF-TNG follow-up of LSQ15bjb
  45. GRB 151021A: Skynet PROMPT-CTIO/DSO17 observations of the optical afterglow
  46. LIGO/Virgo G194575: Kanata/J-GEM optical follow-up
  47. GRB 151022A: OSN optical upper limit
  48. GRB 151023A: Swift/UVOT Upper Limits
  49. GRB 151022A: Swift/UVOT Upper Limits
  50. LIGO/Virgo G194575: RATIR Observations of Nearby Galaxies in the 1sigma Error Region
  51. LIGO/Virgo G194575: RATIR Observations of Nearby Galaxies in the 1sigma Error Region
  52. GRB 151022A: MITSuME Okayama upper limits
  53. GRB 151022A: Mondy optical upper limit
  54. GRB 151022A: Kanata/HOWPol optical observation
  55. GRB 151022A: MASTER-Ural observations
  56. GRB 151021A: MITSuME Okayama upper limits
  57. GRB 151021A: MASTER-NET bright OT detection
  58. GRB 151021A: Optical counterpart and redshift from X-shooter
  59. LIGO/VIRGO G184098 : PESSTO classifications of PanSTARRS transients in the northern region
  60. GRB 151006A: Mondy optical upper limit
  61. GRB 151006A: MITSuME Akeno optical upper limits
  62. GRB 151006A: OSN optical upper limit
  63. GRB 151006A: Swift/UVOT Upper Limits
  64. GRB 151006A: MITSuME Okayama upper limits
  65. GRB 151006A: Kanata/HOWPol optical imaging polarimetry
  66. LIGO/Virgo G184098: ongoing Pan-STARRS search for optical transients
  67. Trigger 657564 / GRB 151004A: Swift/UVOT Upper Limits
  68. Swift Trigger 657564: MASTER-NET early optical observations.
  69. LIGO/Virgo G184098: MASTER OTs detection and Scenario Machine prediction
  70. GRB 151001B: Swift/UVOT Upper Limits
  71. GRB 151001B: MASTER-NET early optical observations.
  72. GRB 151001A: NOT imaging
  73. GRB 151001A: Swift detection of a burst with an optical counterpart
  74. GRB 150925A: Swift/UVOT Upper Limits
  75. LIGO/Virgo G184098: ASKAP followup
  76. LIGO/Virgo G184098: ongoing Pan-STARRS search for optical transients
  77. LIGO/Virgo G184098: optical transient search with Kiso Schmidt telescope and KWFC on behalf of J-GEM collaboration
  78. LIGO/Virgo G184098: TAROT network optical observations
  79. LIGO/Virgo G184098: Pan-STARRS1 observations of the northern sky region
  80. LIGO/Virgo G184098: Keck II DEIMOS Spectra of iPTF Optical Candidates
  81. LIGO/Virgo G184098: iPTF Optical Transient Candidates
  82. LIGO/Virgo G184098: TAROT La Silla Observatory optical observations (TZAC)
  83. GRB 150910A: AAO optical observations
  84. GRB 150915A: NOT observations of a brightening afterglow
  85. GRB 150915A: Swift UVOT upper limits
  86. GRB 150910A: Mt. Terskol observatory optical observations
  87. GRB 150910A: TSHAO optical observations
  88. GRB 150915A: VLT/X-shooter redshift
  89. GRB 150915A: GROND detection of an optical counterpart candidate
  90. GRB 150915A: MASTER-NET optical observations
  91. GRB 150910A: Continued RATIR Observations
  92. GRB 150912A: Swift-XRT and UVOT observations
  93. GRB 150910A: Mt. Terskol observatory optical observation
  94. GRB 150912A: MITSuME Ishigakijima upper limits
  95. GRB 150911A: WHT optical imaging
  96. GRB 150910A: RATIR Observations
  97. GRB 150910A: MITSuME Ishigakijima Optical Observation after 2 days
  98. GRB 150912A: MASTER-IAC optical observations
  99. GRB150910A: P60 Observations
  100. GRB 150911A: Swift/UVOT Upper Limits

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