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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"

41698 results found.

  1. GRB030329: ROTSE network observes steepening of decay curve
  2. GRB 030329, optical photometry
  3. GRB 030329: Optical decay and synthesis
  4. GRB030329 optical observations
  5. GRB030329: optical spectroscopy with the TNG
  6. GRB 030329: Radio Observations
  7. GRB 030329, optical spectroscopy
  8. GRB 030329: still bright
  9. GRB 030329: Optical pre-Imaging
  10. GRB 030329: visual observations
  11. GRB 030329: Upper limit from 5.6 hours before trigger
  12. GRB030328: R optical observation
  13. GRB030328: X-ray Afterglow Observed with Chandra
  14. GRB 030323: Gemini South VRI obsevations.
  15. GRB030329: Optical observations
  16. GRB030329 optical observations
  17. GRB030329:optical observations by MASTER
  18. GRB 030329: optical observations
  19. GRB 030329, R-band observations
  20. GRB 030329: OT B and R photometry, decline rate
  21. GRB030329: Upper limits from recent and historical observations.
  22. GRB030329 (=H2652): A Long, Extremely Bright GRB Localized by the HETE WXM and SXC
  23. RXTE detection of GRB 030329 afterglow
  24. GRB 030329: Optical Afterglow Observations
  25. GRB 030329: precise position from Kyoto images
  26. GRB 030328 Optical Observations
  27. GRB030328: Decay index
  28. GRB 030328: Optical observations
  29. GRB 030328: optical observations
  30. GRB 030329: Optical afterglow fading
  31. GRB 030329: Optical afterglow candidate
  32. GRB 030329: OT candidate
  33. GRB 030329: Optical afterglow candidate
  34. GRB 030328: OT photometry
  35. GRB030328: optical spectroscopy at TNG
  36. GRB030328: optical photometry at the TNG
  37. VLT spectra of GRB 030328
  38. GRB 030328, optical spectroscopy
  39. GRB 030328, optical observations
  40. GRB030328 (=H2650): A Long, Bright GRB Localized by the HETE WXM and SXC
  41. GRB 030328: Optical observations
  42. GRB 030328: Finding chart
  43. GRB 030328: Optical afterglow candidate
  44. GRB030323 optical observations
  45. GRB030131, BVRcIc field photometry
  46. IPN triangulation of GRB030325 (final analysis)
  47. GRB030323: Detection on 2003/03/24
  48. GRB 030323: SARA Optical Observations
  49. IPN triangulation of GRB030325 (single small error box)
  50. GRB030324, optical observations
  51. GRB030324, optical observations
  52. GRB 030324: TAROT optical observations
  53. GRB030323: V, R, I photometry
  54. GRB 030324 (HETE #2641): Optical observations
  55. GRB030324, Optical Observations
  56. GRB030323: Upper limits from recent and historical observations.
  57. GRB030323 (=H2640): A Faint, Long GRB Localized by the HETE WXM and SXC
  58. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  59. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  60. VLT/FORS2 spectra of GRB 030323
  61. GRB030323, ROTSE-III detection of possible optical counterpart
  62. GRB030323, optical observations
  63. GRB030324, BVRcIc field photometry
  64. GRB030323, possible optical counterpart
  65. GRB030323, BVRcIc field calibration
  66. GRB 030324 optical observations
  67. GRB 030320: Optical Observations
  68. GRB 030324, optical observations
  69. IPN triangulation of GRB030320 (small error box)
  70. IPN triangulation of GRB030320
  71. GRB030226, addendum to GCN 1892
  72. IPN upper limit to a GRB associated with SN2003L
  73. GRB 030227: Optical limit at RIKEN
  74. GRB 030226 Optical observations
  75. IPN triangulation of GRB030306 (single small error box - REVISED)
  76. GRB030226: Optical observations at Asiago
  77. IPN triangulation of GRB030306 (single small error box)
  78. IPN triangulation of GRB030306 (two small error boxes)
  79. GRB 030226: Optical observations
  80. GRB030226: Analysis of Chandra data
  81. GRB 030227: Optical observations
  82. GRB030226, BVRc observations
  83. Chandra detection of the X-ray afterglow of GRB 030226
  84. GRB 030226, further optical/NIR imaging
  85. GRB030227, optical observations
  86. GRB 030226: Ic Observations
  87. GRB030227: Kiso optical upper limit
  88. GRB030227, BVRcIc field photometry
  89. GRB030226, BVRcIc field calibration
  90. GRB 030227 optical afterglow
  91. GRB 030228, optical observations
  92. GRB 030226: Steep Decline
  93. GRB 030227: Confirmed Optical Afterglow (S1-A)
  94. GRB 030226: R band polarimetric observations
  95. GRB 030226: Optical observations
  96. GRB 030227: fading of candidate optical afterglow 'S1-A'
  97. GRB030227:Optical observations
  98. GRB 20030226: Upper limits from recent and historical observations
  99. GRB 030227, possible optical counterpart of XMM-Newton source
  100. GRB030227 - faint tentative OT candidate

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