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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"

32715 results found.

  1. GRB030323, optical observations
  2. GRB030323, possible optical counterpart
  3. GRB 030324 optical observations
  4. GRB 030320: Optical Observations
  5. IPN triangulation of GRB030320 (small error box)
  6. IPN triangulation of GRB030320
  7. GRB030226, addendum to GCN 1892
  8. IPN upper limit to a GRB associated with SN2003L
  9. GRB 030227: Optical limit at RIKEN
  10. GRB 030226 Optical observations
  11. IPN triangulation of GRB030306 (single small error box - REVISED)
  12. GRB030226: Optical observations at Asiago
  13. IPN triangulation of GRB030306 (two small error boxes)
  14. GRB 030226: Optical observations
  15. GRB030226: Analysis of Chandra data
  16. GRB 030227: Optical observations
  17. GRB030226, BVRc observations
  18. Chandra detection of the X-ray afterglow of GRB 030226
  19. GRB 030226, further optical/NIR imaging
  20. GRB 030226: Ic Observations
  21. GRB030227: Kiso optical upper limit
  22. GRB030227, BVRcIc field photometry
  23. GRB030226, BVRcIc field calibration
  24. GRB 030227 optical afterglow
  25. GRB 030226: Steep Decline
  26. GRB 030227: Confirmed Optical Afterglow (S1-A)
  27. GRB 030226: R band polarimetric observations
  28. GRB 030226: Optical observations
  29. GRB 030227: fading of candidate optical afterglow 'S1-A'
  30. GRB030227:Optical observations
  31. GRB 20030226: Upper limits from recent and historical observations
  32. GRB 030227, possible optical counterpart of XMM-Newton source
  33. GRB030227 - faint tentative OT candidate
  34. GRB 030226, optical observations
  35. XMM-Newton observation of GRB030227
  36. GRB 030227: Kyoto optical observation
  37. GRB 030226, optical light curve
  38. GRB 030226 spectroscopy
  39. Possible break in the GRB 030226 light curve
  40. GRB030226: optical observation
  41. GRB 030226: Confirmed decay index
  42. GRB030226: ESI spectroscopy
  43. GRB030226 (=U10893): A Long GRB Localized by the HETE WXM and SXC
  44. Two absorption systems in GRB 030226
  45. GRB 030226, optical observations
  46. GRB030226: optical observations and refined redshift
  47. GRB 030226, optical observations
  48. GRB 030226: Optical afterglow
  49. GRB 030217: Optical Observations at 4, 5, and 6 Days
  50. GRB: Non-Referencing of GCN Circulars.
  51. GRB030217: optical observations
  52. IPN triangulation of GRB030217 (small error box)
  53. GRB030115, WSRT radio observations - correction to GCN 1864
  54. GRB 030131: marginal optical detection
  55. GCN/INTEGRAL Mistake Fixed
  56. GRB 030204: Optical Observations
  57. GRB030204 field photometry
  58. GRB020819: Kiso R and I band observations
  59. GRB 030204: Correction to GCN 1856
  60. GRB030131: Candidate Optical Afterglow
  61. GRB 030115: Optical Observations
  62. GRB 030204, optical observations
  63. GRB 030131, optical observations
  64. GRB030131: Kiso optical limit for corrected position
  65. GRB030131: Optical limits for corrected position
  66. GRB 030131: afterglow candidate
  67. GRB 030115, late-time optical observations
  68. Type Ic SN2003L (SN/GRB?), optical spectrum
  69. GRB 020819: Host galaxy at Radio Position
  70. IPN triangulation of GRB030131 - CORRECTION
  71. IPN triangulation of GRB030131
  72. GRB030131: Optical limit
  73. GRB 030131 optical observations
  74. GRB030131: refined position
  75. GRB 030131 optical observations
  76. GRB030115: 1.2 mm upper limits with MAMBO @ IRAM 30m
  77. GRB030115 submm upper limit
  78. GRB 030115: Further IR observations with IRSF/SIRIUS
  79. Publicizing GRB Discoveries - A Message from NASA HQ
  80. GRB 030115, simultaneous observations by BOOTES-1
  81. GRB 030115: IR observations with IRSF/SIRIUS
  82. GRB030115: R-band counterpart of IR candidate
  83. GRB030115, afterglow candidate
  84. GRB 021211: R-band observations at late-time
  85. GRB030115: Optical Observations, Swiss Telescope at La Silla (ESO, Chile)
  86. IPN triangulation of GRB030115B (small error box)
  87. GRB 030115 : Possible IR counterpart
  88. GRB 030115: Radio Observations
  89. GRB030115 (=H2533): A Long GRB Localized by the HETE WXM and SXC
  90. Distribution of INTEGRAL SPI-ACS triggers for GRB bursts
  91. ANNOUNCEMENT ON INTEGRAL GRB ALERTS
  92. Distribution of INTEGRAL SPI-ACS triggers
  93. GRB030115: TAROT optical observations
  94. GRB 021211: VLT spectrum
  95. GRB 030115: APO Optical Observations
  96. GRB 030115, no optical candidate
  97. GRB 030115, optical observations
  98. GRB 030115, optical candidate
  99. IPN triangulation of GRB030109 (annulus)
  100. IPN triangulation of GRB030105 (large error box)

Advanced

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