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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"

32542 results found.

  1. GRB 030328: OT photometry
  2. GRB030328: optical spectroscopy at TNG
  3. GRB030328: optical photometry at the TNG
  4. VLT spectra of GRB 030328
  5. GRB 030328, optical spectroscopy
  6. GRB 030328, optical observations
  7. GRB030328 (=H2650): A Long, Bright GRB Localized by the HETE WXM and SXC
  8. GRB 030328: Optical observations
  9. GRB 030328: Finding chart
  10. GRB030323 optical observations
  11. GRB030131, BVRcIc field photometry
  12. IPN triangulation of GRB030325 (final analysis)
  13. GRB030323: Detection on 2003/03/24
  14. GRB 030323: SARA Optical Observations
  15. IPN triangulation of GRB030325 (single small error box)
  16. GRB030324, optical observations
  17. GRB030324, optical observations
  18. GRB 030324: TAROT optical observations
  19. GRB030323: V, R, I photometry
  20. GRB 030324 (HETE #2641): Optical observations
  21. GRB030324, Optical Observations
  22. GRB030323: Upper limits from recent and historical observations.
  23. GRB030323 (=H2640): A Faint, Long GRB Localized by the HETE WXM and SXC
  24. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  25. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  26. VLT/FORS2 spectra of GRB 030323
  27. GRB030323, ROTSE-III detection of possible optical counterpart
  28. GRB030323, optical observations
  29. GRB030323, possible optical counterpart
  30. GRB 030324 optical observations
  31. GRB 030320: Optical Observations
  32. IPN triangulation of GRB030320 (small error box)
  33. IPN triangulation of GRB030320
  34. GRB030226, addendum to GCN 1892
  35. IPN upper limit to a GRB associated with SN2003L
  36. GRB 030227: Optical limit at RIKEN
  37. GRB 030226 Optical observations
  38. IPN triangulation of GRB030306 (single small error box - REVISED)
  39. GRB030226: Optical observations at Asiago
  40. IPN triangulation of GRB030306 (two small error boxes)
  41. GRB 030226: Optical observations
  42. GRB030226: Analysis of Chandra data
  43. GRB 030227: Optical observations
  44. GRB030226, BVRc observations
  45. Chandra detection of the X-ray afterglow of GRB 030226
  46. GRB 030226, further optical/NIR imaging
  47. GRB 030226: Ic Observations
  48. GRB030227: Kiso optical upper limit
  49. GRB030227, BVRcIc field photometry
  50. GRB030226, BVRcIc field calibration
  51. GRB 030227 optical afterglow
  52. GRB 030226: Steep Decline
  53. GRB 030227: Confirmed Optical Afterglow (S1-A)
  54. GRB 030226: R band polarimetric observations
  55. GRB 030226: Optical observations
  56. GRB 030227: fading of candidate optical afterglow 'S1-A'
  57. GRB030227:Optical observations
  58. GRB 20030226: Upper limits from recent and historical observations
  59. GRB 030227, possible optical counterpart of XMM-Newton source
  60. GRB030227 - faint tentative OT candidate
  61. GRB 030226, optical observations
  62. XMM-Newton observation of GRB030227
  63. GRB 030227: Kyoto optical observation
  64. GRB 030226, optical light curve
  65. GRB 030226 spectroscopy
  66. Possible break in the GRB 030226 light curve
  67. GRB030226: optical observation
  68. GRB 030226: Confirmed decay index
  69. GRB030226: ESI spectroscopy
  70. GRB030226 (=U10893): A Long GRB Localized by the HETE WXM and SXC
  71. Two absorption systems in GRB 030226
  72. GRB 030226, optical observations
  73. GRB030226: optical observations and refined redshift
  74. GRB 030226, optical observations
  75. GRB 030226: Optical afterglow
  76. GRB 030217: Optical Observations at 4, 5, and 6 Days
  77. GRB: Non-Referencing of GCN Circulars.
  78. GRB030217: optical observations
  79. IPN triangulation of GRB030217 (small error box)
  80. GRB030115, WSRT radio observations - correction to GCN 1864
  81. GRB 030131: marginal optical detection
  82. GCN/INTEGRAL Mistake Fixed
  83. GRB 030204: Optical Observations
  84. GRB030204 field photometry
  85. GRB020819: Kiso R and I band observations
  86. GRB 030204: Correction to GCN 1856
  87. GRB030131: Candidate Optical Afterglow
  88. GRB 030115: Optical Observations
  89. GRB 030204, optical observations
  90. GRB 030131, optical observations
  91. GRB030131: Kiso optical limit for corrected position
  92. GRB030131: Optical limits for corrected position
  93. GRB 030131: afterglow candidate
  94. GRB 030115, late-time optical observations
  95. Type Ic SN2003L (SN/GRB?), optical spectrum
  96. GRB 020819: Host galaxy at Radio Position
  97. IPN triangulation of GRB030131 - CORRECTION
  98. IPN triangulation of GRB030131
  99. GRB030131: Optical limit
  100. GRB 030131 optical observations

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