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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"

4572 results found.

  1. GRB 041211: KAIT observations
  2. GRB970815: Discovery of Optical Afterglow
  3. GRB 040924: Afterglow Color
  4. GRB 041016: Optical limits
  5. Konus-Wind observation of a series SGR 1806-20 bursts on 041005
  6. GRB040924,optical observation
  7. GRB040924,optical observation
  8. GRB040924, RTT150 optical observation
  9. GRB 040924: Subaru NIR observation
  10. GRB 040924, optical follow-up
  11. GRB 040924(=H3564): A Short, Bright GRB Localized in Real Time by HETE
  12. GRB040912(=H3557): Chandra Candidate X-ray Afterglow
  13. IBAS GRB Alerts 1978-1980
  14. GRB040903 - A XRF?
  15. GRB040825A: optical limit before GRB
  16. GCN GRB OBSERBATION REPORT
  17. GRB040825B: Correction to GCN 2657
  18. XRF 040812: optical observation at VLT
  19. XRF040701: Second-Epoch Chandra Observations
  20. XRF040701: First-Epoch Chandra Observations
  21. GRB040624, optical observations
  22. MASTER: GRB 040624 optical observation after 0,48d
  23. GRB 040624 - A long GRB detected with INTEGRAL
  24. IPN Summary of SGR1806-20 Activity in 2004
  25. SGR 1806-20, potential NIR counterpart
  26. GRB 040403: Optical Observations
  27. GRB 040403: Optical observations
  28. Summary of recent bursts from SGR 1806-20 detected by INTEGRAL
  29. GRB040323: NIR Observations and Variable Object
  30. GRB 040323, a dark GRB ?
  31. GRB040223: Deep NIR NTT data re-analysis
  32. IBAS results on a burst from SGR1806-20
  33. GRB 040228 Optical observations
  34. GRB 040228 (=H3066?,=H3067?): A Long GRB Localized by the HETE-2 WXM
  35. GRB 040223: REM IJK Observations
  36. GRB031220: 2nd Chandra observation and X-ray afterglow candidate
  37. GRB 031220: Optical observations of Chandra X-ray sources
  38. GRB031220(=H2976): TNG R-band Observation of the Chandra X-ray Sources
  39. GRB031220(=H2976): Observation with the Chandra X-ray Observatory
  40. IPN triangulation of GRB031219 (large error box)
  41. GRB031220: Palomar Observations
  42. IPN triangulation of GRB031201 (large error box)
  43. IPN triangulation of GRB031111 (=H2924): small error box
  44. IPN triangulation of GRB031108 (large error box)
  45. IPN triangulation of GRB031026B (large error box)
  46. IPN triangulation of GRB030922B (large error box)
  47. XRF 030723: Detection of the likely host galaxy
  48. XRF030824 (=H2821): An X-Ray Flash Localized by the HETE WXM
  49. GRB030913: Subaru Optical Observations
  50. GRB030913: AAVSO optical observations
  51. GRB 030913: Optical limit at RIKEN
  52. XRF030824: Optical observations
  53. INTEGRAL ToO OBSERVATIONS OF SGR1806-20: CALL FOR CORRELATED OBSERVATIONS
  54. XRF030824: optical observations
  55. XRF030723: optical observations
  56. H2768, H2770, and H2771: Three Bursts from SGR1806-20
  57. IPN triangulation of GRB030715 (two large error boxes)
  58. GRB030329: second XMM-Newton observation
  59. GRB030528(=H2724): Observations with the Chandra X-ray Observatory
  60. GRB 030329: optical observations
  61. GRB 030329: optical photometry at Belesta observatory (France)
  62. GRB030329, Optical observations
  63. GRB030329: XMM-Newton observation
  64. GRB030324: Further Observations of the Candidate Optical Afterglow
  65. GRB030519B (=H2716): Peak Fluxes, Fluences, and Energy Spectrum
  66. GRB 030418: Second Epoch Optical Observations with Magellan
  67. GRB030519B (=H2716): A Long, Bright GRB Localized by the HETE WXM
  68. GRB 030429: confirmation of afterglow candidate
  69. GRB030329, SPM optical observations
  70. GRB 030329, the review of the sky area in plate archive (1950-1998)
  71. GRB 030329: Spectral Evolution of SN 2003dh
  72. GRB030329: VR Photometry at TNG
  73. GRB030324: Candidate Optical Afterglow
  74. IPN triangulation of GRB050403 (small error box)
  75. GRB030329: final R-band light curve by MASTER
  76. GRB 030329, BRI photometry
  77. GRB 030329: Additional Mt. Laguna Optical Observations
  78. GRB 030329: Correction to GCN 2056
  79. GRB 030329: fitting parameters and re-brightening
  80. GRB 030329: optical observations
  81. GRB 030324, optical search
  82. GRB030329 (=H2652): A Long, Extremely Bright GRB Localized by the HETE WXM and SXC
  83. GRB030324 optical observation
  84. Possible GRB030323 localized by INTEGRAL
  85. GRB030323: Detection on 2003/03/24
  86. IPN triangulation of GRB030325 (single small error box)
  87. GRB030324, optical observations
  88. GRB030324, optical observations
  89. GRB030324, Optical Observations
  90. GRB030323 (=H2640): A Faint, Long GRB Localized by the HETE WXM and SXC
  91. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  92. VLT/FORS2 spectra of GRB 030323
  93. GRB030323, ROTSE-III detection of possible optical counterpart
  94. GRB030323, optical observations
  95. IPN triangulation of GRB030320
  96. GRB 030227: Optical limit at RIKEN
  97. GRB 030227: Optical observations
  98. GRB030227: Kiso optical upper limit
  99. GRB 030226: Steep Decline
  100. GRB030226: Candidate optical afterglow

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