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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"
  1. GRB 080205: GAO 150cm telescope Optical limit
  2. GRB 080207, Swift-BAT refined analysis
  3. GRB 080207: Optical limits from Gemini-South
  4. GRB 080205: RTT150 optical observations
  5. Swift detection of AX J1749.1-2639
  6. GRB 080207: Super-LOTIS observations
  7. GRB 080207, Swift-BAT refined analysis
  8. Swift Trigger 302777 is not a GRB
  9. GRB080207: RTT150 Optical Observations
  10. GRB 080207: REM NIR observations
  11. GRB080207: Swift/UVOT refined analysis
  12. GRB 080207: TAROT Calern observatory optical observations
  13. GRB 080207: Swift-XRT Refined Analysis
  14. GRB 080207: Enhanced Swift-XRT position
  15. GRB 080207: Swift detection of a burst
  16. Konus-Wind observation of GRB 080204
  17. GRB 080205 optical upper limit
  18. GRB 080205: MASTER optical observation
  19. GRB 080205: optical observation
  20. VLA radio upper limit on GRB 080205
  21. INT+WFC R-band observations of GRB 080205
  22. GRB 080205, Swift-BAT refined analysis
  23. IPN localization of very hard GRB 080204
  24. GRB 080205: Swift XRT refined analysis
  25. GRB 080205: OA evolution from KAIT observations
  26. GRB 080205: Swift/UVOT observations
  27. GRB 080205: Enhanced Swift-XRT position
  28. GRB 080205: KAIT OA detection
  29. GRB 080205: Swift detection of a burst
  30. Swift-BAT Trigger #302454, correction of GCN notice, update on AX J1749.1-2639
  31. GRB 080130: Swift-BAT refined analysis
  32. GRB 080130: further Swift XRT observations confirm fading source
  33. GRB 080129: Swift/UVOT Refined Upper Limits
  34. Swift/UVOT observations of GRB080130
  35. GRB 080130: REM NIR observations
  36. GRB 080130(?): Swift XRT observation
  37. GRB 080130?: Detection of a possible burst by BATSS
  38. GRB 080129: Optical observations from OSN
  39. GRB 080129: Swift-XRT refined analysis
  40. X-ray transient in NGC 2770: RTT150 optical observations
  41. GRB 080129: KAIT optical limits
  42. GRB 080123: Early afterglow detection with BATSS (BAT Slew Survey)
  43. GRB 080129: optical limit by Pi of the Sky
  44. GRB 080129, Swift-BAT refined analysis
  45. GRB 080129: TAROT La Silla observatory optical observations
  46. GRB 080129: Gemini-South photometry
  47. GRB 080129: GROND detection in all bands, and fading
  48. GRB 080129: GROND detection of the optical/NIR afterglow, and fading
  49. GRB 080129: Enhanced Swift-XRT position
  50. GRB 080129: Gemini-South Imaging Observations
  51. GRB 080129: Swift XRT position
  52. GRB 080129 (?): UVOT Upper Limits
  53. GRB 080129 (?): Swift detection of a possible burst
  54. A new website of high-level data products for Swift GRBs
  55. GRB 080121: Upper limit on X-ray afterglow
  56. GRB 080123 : Suzaku WAM observation of the prompt emission
  57. Swift trigger(=301779) is not a GRB
  58. Transient 080109/SN 2008D: Spectroscopic Evolution
  59. GRB 080122: pseudo-z= 1.93 from prompt emission spectrum
  60. Konus-Wind observation of GRB 080122
  61. GRB 080122 : Suzaku WAM observation of the prompt emission
  62. GRB 080121: Swift/UVOT upper limits
  63. SNe 2008D and 2007uy: Chandra Detections
  64. GRB 080121 position was incorrect
  65. GRB 080121: Enhanced Swift-XRT position
  66. Two non-burst Swift SubThreshold triggers
  67. Transient 080109/SN 2008D: Spectroscopic Evolution and Re-Classification
  68. IPN triangulation of GRB080122
  69. GRB 080121: Nearby SDSS galaxies
  70. GRB 080121: Swift-BAT detection of a very weak, short burst
  71. GRB 080123: Swift-XRT refined analysis
  72. GRB 080123: Swift/UVOT refined analysis
  73. X-ray transient in NGC 2770: RTT150 optical observations
  74. GRB 080123, Swift-BAT refined analysis
  75. GRB 080123: Enhanced Swift-XRT position
  76. GRB 080123: Swift detection of a short burst
  77. GRB 080120: GROND confirmation of the optical afterglow
  78. XRF 080109 / SN 2008D: GMRT radio observation at 1280 MHz
  79. VLA radio upper limit on GRB 080120
  80. GRB 080120: Swift-XRT refined analysis
  81. UVOT detection of GRB080120
  82. GRB 080120: GROND detection
  83. GRB 080120 : Planned XMM-Newton observation
  84. GRB080120: Swift XRT position
  85. GRB 080120: a long GRB detected by INTEGRAL
  86. XRF 080109 / SN 2008D: 1.4 GHz WSRT Radio Observations
  87. Transient in NGC2770 / SN2008D: Metallicity of nearby HII regions
  88. Transient XRF 080109 / SN 2008D: Mount Abu NIR observations
  89. XRF 080109 / SN 2008D: WSRT Radio Detection
  90. Transient 080109/ SN 2008D, metallicity of the host galaxy
  91. Transient 080109/ SN 2008D, IR Spectrum
  92. XRF 080109 / SN 2008D: optical observations
  93. NGC 2770B has the same redshift as NGC 2770
  94. Swift UVOT Monitoring of the SN 2008D Brightening (Transient in NGC 2770)
  95. XRF 080109 / SN 2008D: spectroscopic evolution
  96. XRF 080109 / SN 2008D: UKIRT JHK imaging
  97. optical observations, XRT in NGC 2770
  98. XRF 080109/SN 2008D: PROMPT Optical Imaging
  99. Gemini-South observations of XRF 080109 / SN 2008D
  100. Swift observations of the X-ray transient in NGC 2770 (aka SN2008D)

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