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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"

23561 results found.

  1. Swift J185003.2-005627: Swift-XRT/UVOT refined analysis
  2. Swift J185003.2-005627: TAROT La Silla observatory optical observations
  3. Swift J185003.2-005627: TAROT Calern observatory optical observations
  4. Swift J185003.2-005627: Swift detection of a burst from a new Galactic transient
  5. GRB 110604A: final update on Swift-XRT observations
  6. SGR 1E 1841-045: Swift detection of a soft gamma repeater burst
  7. IPN triangulation of GRB110618A (long duration, extremely intense)
  8. GRB 110610A: 1.23m CAHA optical observations
  9. GRB 110610A: Swift/UVOT Upper Limits
  10. GRB 110610A: Enhanced Swift-XRT position
  11. GRB 110610A: Swift-BAT refined analysis
  12. Swift detection of the X-ray afterglow of GRB 110604A
  13. GRB 110610A: Swift detection of a burst
  14. GRB 110604A Detection by IPN Spacecraft and Swift-BAT
  15. GMRT detection of GRB 110328A
  16. GRB 110530A: Swift/UVOT Detection of a Fading Afterglow
  17. GRB 110530A: Enhanced Swift-XRT position
  18. GRB 110530A: NOT optical observations
  19. GRB110530A: MITSuME Okayama Optical Observation
  20. GRB 110529A: Fermi GBM detection
  21. GRB 110530A: Swift detection of a burst with an optical afterglow
  22. LAT Observations of GRB110529A
  23. EVLA afterglow limits on the high z GRB090429B
  24. Swift J1644+57/GRB 110328A, Additional HST Observations
  25. GRB 110521A: MASTER prompt optical limit
  26. GRB 110521A: Swift/UVOT Upper Limits
  27. GRB 110520A: NOT optical follow-ups
  28. GRB 110521A - NOT optical observation
  29. GRB 110521A: Enhanced Swift-XRT position
  30. GRB 110521A: MASTER synchronous and early optical observations limit
  31. Swift/UVOT observations of GRB110520A
  32. GRB 110521A: Swift detection of a burst
  33. GRB 110520A: IAC80 I-band observations
  34. GRB 110520A: Enhanced Swift-XRT position
  35. GRB 110520A: WHT IR observations
  36. GRB 110520A - NOT optical observation
  37. GRB 110520A: Skynet/DAO optical observations
  38. GRB 110520A: Liverpool Telescope Observations
  39. GRB 110520A: TAROT Calern observatory optical observations
  40. GRB 110520A: Swift detection of a burst
  41. IPN localization of bright GRB 110518A
  42. Radio observations of GRB 110428A with the EVLA
  43. GRB 110519A, Swift-BAT refined analysis
  44. GRB 110519A: Swift detection of a burst
  45. GRB 110426A: Fermi GBM detection
  46. GRB 110503A: TAROT Calern observatory optical observations
  47. GRB 110503A: Jet Break seen from TLS
  48. GRB 110503A: optical observation in CrAO
  49. GRB 110503A: Centimeter observation from EVLA
  50. GRB 110503A: Millimeter observation from SMA
  51. GRB 110503A: SARA-N Observations and Photometric Calibration
  52. GRB 110503A: Swift/UVOT Observations
  53. GRB 110503A: PAIRITEL NIR Detection
  54. GRB 110503A - TLS Afterglow Observations
  55. GRB 110503A: Enhanced Swift-XRT position
  56. GRB 110503A: Swift detection of a burst with a bright optical counterpart
  57. GRB 110426A: Swift/XRT non-detection
  58. GRB 110428A : X-ray afterglow confirmation
  59. GRB 110422A: optical observations in CrAO
  60. GRB 110428A : Swift-XRT observations
  61. GRB 110428A: Fermi-LAT Detection
  62. GRB 110426A: MASTER synchronous with MAXI/GSC observations
  63. GRB 110422A: optical observations in CrAO, second epoch
  64. GRB 110422A: Herschel observation scheduled
  65. GRB110422A: NOT optical follow-ups
  66. GRB 110422A: optical observations in CrAO
  67. GRB110422A: MITSuME Ishigakijima Optical Observation
  68. GRB 110422A: Further NOT observation
  69. GRB 110422A: Swift/UVOT Detection of optical afterglow
  70. GRB 110422A: THO optical observations
  71. GRB 110422A: Enhanced Swift-XRT position
  72. GRB 110422A: TNG optical observations
  73. GRB 110422A: SAO RAS optical observations
  74. GRB 110422A: NOT optical observation
  75. GRB 110422A: Swift-BAT refined analysis
  76. GRB 110422A: Mondy optical observations
  77. GRB 110422A: Swift detection of a burst
  78. GRB 110420B: Swift/UVOT Upper Limits
  79. GRB110420A: GROND detection of the Optical/NIR Afterglow Candidate
  80. GRB 110420B: Swift-XRT afterglow candidate retraction
  81. GRB 110420B, GROND observations
  82. GRB 110420A Swift/UVOT Observations
  83. GRB 110420B: Swift-XRT afterglow candidate
  84. GRB 110420B: Swift detection of a short hard burst
  85. GRB 110420A: Enhanced Swift-XRT position
  86. GRB 110420A: Swift detection of a burst with optical counterpart
  87. GRB110414A: MITSuME Ishigakijima Optical upper limits
  88. GRB 110414A: GROND upper limits
  89. GRB110414A: MITSuME Okayama Optical upper limits
  90. GRB 110414A: Swift/UVOT Upper limits
  91. GRB 110414A: Enhanced Swift-XRT position
  92. GRB 110328A / Swift J164449.3+573451: WISE quiescent source upper limit
  93. GRB 110414A: Swift detection of a burst
  94. GRB 110411A: PAIRITEL NIR Upper Limits
  95. GRB 110411A: Swift/UVOT Upper Limits
  96. GRB 110412A: Swift detection of a burst
  97. GRB 110411A: Enhanced Swift-XRT position
  98. GRB 110411A: Swift detection of a burst
  99. GRB 110328A / Swift J164449.3+573451: MASTER pre, prompt and follow-up observations
  100. GRB 110407A:VLF observations on 20.27kHz

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