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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.

Advanced Search Examples (click to copy):

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

16160 results found.

  1. GRB 120422A: Zadko observatory - Gingin optical observations
  2. GRB 120422A: Gemini observations
  3. GRB 120419A: Swift-XRT and UVOT observations
  4. GRB 120404A: optical observations in Mondy observatory
  5. GRB 120404A: optical observations
  6. GRB 120404A, Optical Observations
  7. GRB 120404A: SMARTS optical/IR observations
  8. GRB120404A: MOA optical observations of the initial rise afterglow
  9. GRB 120404A: VLT/X-shooter redshift confirmation
  10. GRB 120404A: Swift/UVOT Detection
  11. GRB 120404A: MITSuME Ishigakijima Optical Observation
  12. GRB 120404A: MITSuME Okayama Optical Observation
  13. GRB 120404A : TNT optical observation
  14. GRB 120401A: GROND Detection of an optical/NIR afterglow candidate
  15. GRB 120402B: MASTER early OT limit
  16. GRB 120403B: TAROT La Silla observatory optical observations
  17. GRB 120404A: Gemini-N Redshift
  18. GRB 120404A: MITSuME Akeno Optical upper limits
  19. GRB 120404A: MASTER early OT limit
  20. GRB 120404A: Faulkes Telescope North afterglow confirmation
  21. GRB 120404A: Swift detection of a burst with an optical counterpart
  22. GRB 120403B: Swift/UVOT Upper Limits
  23. GRB 120402A: optical upper limit
  24. GRB 120320A: optical upper limit in Mondy observatory
  25. GRB 120320A: early optical upper limit
  26. GRB 120403A: MASTER follow up observations
  27. GRB 120402A: MASTER follow up observations
  28. GRB 120326A: Bassano Bresciano Observatory - correction for GCN Cir 13178
  29. GRB 120326A: Cima Rest and Bassano Brescia
  30. GRB 120327A: SMARTS optical/IR afterglow observations
  31. GRB 120326A: HCT optical observations
  32. GRB 120326A: EVLA Observations
  33. GRB120327A - ATCA radio afterglow detection at 34GHz
  34. GRB 120324A: CrAO optical upper limit
  35. GRB 120326A: Bassano Bresciano Observatory lightcurve analisis
  36. GRB 120326A: MITSuME Ishigakijima Optical Observation at 3 days afterthe burst
  37. GRB 120326A: CARMA 3mm detection
  38. GRB 120326A: Bassano Bresciano Observatory optical observations
  39. GRB 120328A: MITSuME Ishigakijima Optical Upper Limits
  40. GRB 120326A: MITSuME Ishigakijima Optical Observation at 2 days afterthe burst
  41. GRB 120327A: MITSuME Ishigakijima Optical Upper Limits at 1 day afterthe burst
  42. Trigger 518853: Swift detection of a probable Galactic transient
  43. GRB 120327A: Zadko optical observations
  44. GRB 120328A: Swift/UVOT Upper Limits
  45. GRB 120326A: Bassano Bresciano Observatory further optical observations
  46. GRB 120327A: MITSuME Ishigakijima Optical Observation
  47. GRB 120326A: MITSuME Ishigakijima Optical Observation
  48. GRB 120327A: NOT optical observations
  49. GRB 120328A: TAROT La Silla observatory optical observations
  50. GRB 120326A: Xinglong TNT further optical observation��correction for GCN Cir 13149)
  51. GRB 120326A: Xinglong TNT further optical observation
  52. GRB 120327A: GTC redshift confirmation
  53. GRB 120327A afterglow detection
  54. GRB 120326A: PAIRITEL NIR Observations
  55. GRB 120326A: Bassano Bresciano Observatory optical observations
  56. GRB 120326A: LOAO R-band Observations
  57. GRB 120326A : SMA submm observation
  58. GRB 120327A: X-shooter redshift
  59. GRB 120327A: Gemini-South redshift
  60. GRB 120327A: TAROT La Silla observatory optical decay
  61. GRB120326A: TNT optical observation
  62. GRB 120327A: IAC80 I-band observations
  63. GRB 120327A: REM NIR and optical observations
  64. GRB 120326A: Maisoncelles Observatory optical observations
  65. GRB 120327A: Liverpool Telescope Observations
  66. GRB 120327A: TAROT La Silla observatory optical detection
  67. GRB 120327A: Swift detection of a burst with an optical counterpart
  68. GRB 120326A: optical observation of GMG
  69. GRB 120326A : LOT optical observation
  70. GRB 120326A: T17 optical observations
  71. GRB 120326A: GTC redshift
  72. GRB 120323A: MASTER follow up observations
  73. GRB 120326A: Optical observations at Crni Vrh
  74. GRB120326A: IAC80 observations
  75. GRB 120326A: Liverpool Telescope observations
  76. Skynet/Dolomiti Observations of GRB120326A
  77. GRB 120326A: TAROT Calern observatory afterglow optical decay
  78. GRB 120326A: TAROT Calern observatory afterglow optical detection
  79. GRB 120326A: ROTSE-III Optical Limits
  80. GRB 120324A: CQUEAN rizY Observation
  81. GRB 120324A: Swift/UVOT Upper Limits
  82. GRB 120324A: TAROT La Silla observatory optical observations
  83. GRB 120324A: Liverpool Telescope optical candidate
  84. Simultaneous optical images of Swift pointing are available by GRT
  85. GRB 120320A: Zadko optical observations
  86. GRB 120229A: Magellan observations and limit on an optical afterglow
  87. GRB 120320A: Swift/UVOT Upper Limits
  88. GRB 120320A: MITSuME Okayama Optical upper limits
  89. GRB 120320A , optical observations
  90. GRB 120320A: BOOTES-4 optical upper limit
  91. GRB 120320A: Gemini-N and UKIRT observations
  92. GRB 120320A: MASTER optical observations
  93. GRB 111228A: possible detection of the SN with the TNG
  94. GRB 120312A: CrAO optical upper limit
  95. GRB 120311A: Optical follow-up
  96. GRB 120311B: Optical follow-up
  97. GRB 120311A: C88 optical limits
  98. GRB 120312A: Swift/UVOT Upper Limits
  99. GRB 120312A: MASTER-NET optical observations
  100. GRB 120312A: NOT observations

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