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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').
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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"

36147 results found.

  1. GRB030528(=H2724): X-ray Afterglow Identified in Second Epoch
  2. IPN triangulation of GRB030607 (annulus)
  3. IPN triangulation of GRB030606 (two alternate error boxes)
  4. GRB 030528: Infrared Observations and the Proposed IR Counterpart
  5. IPN triangulation of GRB030605B (annulus)
  6. GRB 030528: Optical Observations
  7. IPN triangulation of GRB030605 (annulus)
  8. GRB 030528: tentative NIR counterpart
  9. GRB 030528, radio observations
  10. GRB030528(=H2724): Observations with the Chandra X-ray Observatory
  11. GRB030329, further radio observations at GMRT
  12. GRB030528, BVRI field photometry
  13. IPN triangulation of GRB030601 (annulus)
  14. GRB030528: Chandra TOO Planned
  15. GRB 030519B: optical observations.
  16. GRB 030329: optical observations
  17. GRB 030329/SN 2003dh: Jitter Episode
  18. GRB 030528, Teramo optical observation
  19. GRB 030528 Bisei optical observation
  20. GRB030528 (H2724): A long GRB localized by HETE
  21. GRB 030329: Correction to GCN 2254
  22. GRB 030329: Optical Observations
  23. GRB 030528: Optical observations at RIKEN
  24. GRB 030528 (=H2724) Kyoto optical observation
  25. IPN triangulation of GRB030523B (annulus)
  26. GRB 030416: Optical Observations
  27. GRB 030329: Planned XMM-Newton Observation
  28. IPN triangulation of GRB030523 (annulus)
  29. GRB 030329: optical photometry at various french observatories
  30. GRB 030329: optical photometry at Belesta observatory (France)
  31. GRB 030329/SN 2003dh: Possible increase in brightness
  32. GRB 030329: HST ACS Observations of the Host
  33. GRB 030329 Optical Observations
  34. GRB 021004: HST observations
  35. GRB030324: Further Observations of the Candidate Optical Afterglow
  36. IPN triangulation of GRB030519B=H2716 (small error box)
  37. GRB 030418: Second Epoch Optical Observations with Magellan
  38. GRB030519B (=H2716): A Long, Bright GRB Localized by the HETE WXM
  39. IPN triangulation of GRB030519 (annulus)
  40. IPN triangulation of GRB030518C (annulus)
  41. IPN triangulation of GRB030518B (annulus)
  42. IPN triangulation of GRB030518A (annulus)
  43. IPN triangulation of GRB030514 (annulus)
  44. IPN triangulation of GRB030513 (annulus)
  45. IPN triangulation of GRB030509B (annulus)
  46. GRB 030329: Optical limit (contemporaneous imaging)
  47. GRB 030501: final TAROT limits
  48. IPN triangulation of GRB030509 (small errror box)
  49. IPN triangulation of GRB030509 - correction
  50. IPN triangulation of GRB030509 (single error box)
  51. GRB030329: RTT150 optical observations
  52. GRB 030329: Optical limit (contemporaneous photography)
  53. GRB030418, BVRcIc field photometry
  54. GRB 030429: Redshift of neighbor galaxy
  55. GRB030429, BVRcIc field photometry
  56. GRB 030329: High-Resolution Spectroscopy of the Host
  57. GRB030429 (=H2695): A Long GRB Localized by the HETE WXM and SXC
  58. GRB030418 (=H2686): A Long, X-Ray-Rich GRB Localized by the HETE WXM
  59. GRB030429: RTT150 optical observations, a possible host galaxy
  60. IPN triangulation of GRB030506 (annulus)
  61. IPN triangulation of GRB030505B (large error box)
  62. IPN triangulation of GRB030505A (annulus)
  63. GRB030329: RTT150 optical observations and upper limit for a host
  64. GRB 030329: all-sky CCD images by K. Shiokawa immediately after the burst
  65. GRB030501, optical observation
  66. GRB030501C triangulation (annulus)
  67. GRB030329: RTT150 optical observations and upper limit for a host
  68. GRB 030429: Radio Observations
  69. GRB 030429: redshift from VLT spectroscopy
  70. GRB 030429: IR photometry with IRSF/SIRIUS
  71. GRB030501B triangulation (single error box)
  72. GRB 030329 Optical Observations
  73. GRB 030329, BVRI photometry
  74. GRB 030501: TAROT possible candidate counterpart
  75. IPN triangulation of GRB030501 (IBIS event; annulus)
  76. IPN triangulation of GRB030501B (annulus)
  77. GRB 030429: confirmation of afterglow candidate
  78. GRB030429, possible optical counterpart
  79. GRB030501 localized by INTEGRAL
  80. GRB030425: CrAO optical observation
  81. IPN triangulation of GRB030429 (annulus)
  82. IPN triangulation of GRB030428 (two large error boxes)
  83. GRB 030329 Oprical observations in Rozhen observatory
  84. GRB 030429: ROTSE-III observations
  85. GRB 030324: Radio Observations
  86. GRB030329 observed as a sudden ionospheric disturbance (SID)
  87. IPN triangulation of GRB030426 (annulus)
  88. SNeIa AS THE POSSIBLE PROGENITORS OF SHORT-DURATION GRBs.
  89. IPN triangulation of GRB030425 (single error box)
  90. GRB 030329, the review of the sky area in plate archive (1950-1998)
  91. GRB 030329: Spectral Evolution of SN 2003dh
  92. Optical Observations of GRB 030418 with Magellan
  93. GRB 030329: optical spectropolarimetry at VLT
  94. IPN triangulation of GRB030422C (annulus)
  95. IPN triangulation of GRB030422B (annulus)
  96. GRB 030329: wide-field photograph by R. Tamura 1 hr after the burst
  97. GRB030329: optical polarization
  98. IPN triangulation of GRB030422 (two large error boxes)
  99. GRB 030329 3.5 and 6 cm radio observations at RTF-32 telescope
  100. IPN triangulation of GRB030421 (annulus)

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