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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"

45402 results found.

  1. GRB030329 - near contemporaneous optical limits from CONCAM
  2. GRB030329: R and B observations
  3. GRB 030329, optical observations
  4. GRB030329: Optical observations
  5. GRB030328: X-ray Fading and Spectrum Measured with Chandra
  6. GRB030329a: detection by Konus-Wind
  7. GRB030329b: detection by Konus-Wind and Helicon-CoronasF
  8. GRB 030329: Light curve observed during the change of its slope.
  9. GRB030329, BVRcIc field photometry
  10. GRB030329, SPM optical observations
  11. GRB 030329: Optical Decay
  12. Redshift of GRB 030329
  13. GRB030329: ROTSE network observes steepening of decay curve
  14. GRB 030329, optical photometry
  15. GRB 030329: Optical decay and synthesis
  16. GRB030329 optical observations
  17. GRB030329: optical spectroscopy with the TNG
  18. GRB 030329: Radio Observations
  19. GRB 030329, optical spectroscopy
  20. GRB 030329: still bright
  21. GRB 030329: Optical pre-Imaging
  22. GRB 030329: visual observations
  23. GRB 030329: Upper limit from 5.6 hours before trigger
  24. GRB030328: R optical observation
  25. GRB030328: X-ray Afterglow Observed with Chandra
  26. GRB 030323: Gemini South VRI obsevations.
  27. GRB030329: Optical observations
  28. GRB030329 optical observations
  29. GRB030329:optical observations by MASTER
  30. GRB 030329: optical observations
  31. GRB 030329, R-band observations
  32. GRB 030329: OT B and R photometry, decline rate
  33. GRB030329: Upper limits from recent and historical observations.
  34. GRB030329 (=H2652): A Long, Extremely Bright GRB Localized by the HETE WXM and SXC
  35. RXTE detection of GRB 030329 afterglow
  36. GRB 030329: Optical Afterglow Observations
  37. GRB 030329: precise position from Kyoto images
  38. GRB 030328 Optical Observations
  39. GRB030328: Decay index
  40. GRB 030328: Optical observations
  41. GRB 030328: optical observations
  42. GRB 030329: Optical afterglow fading
  43. GRB 030329 follow-up
  44. GRB 030329: Optical afterglow candidate
  45. GRB 030329: OT candidate
  46. GRB 030329: Optical afterglow candidate
  47. GRB 030328: OT photometry
  48. GRB030328: optical spectroscopy at TNG
  49. GRB030328: optical photometry at the TNG
  50. VLT spectra of GRB 030328
  51. GRB 030328, optical spectroscopy
  52. GRB 030328, optical observations
  53. GRB030328 (=H2650): A Long, Bright GRB Localized by the HETE WXM and SXC
  54. GRB 030328: Optical observations
  55. GRB 030328: Optical afterglow candidate
  56. GRB030323 optical observations
  57. GRB030324 optical observation
  58. GRB030131, BVRcIc field photometry
  59. Possible GRB030323 localized by INTEGRAL
  60. IPN triangulation of GRB030325 (final analysis)
  61. GRB030323: Detection on 2003/03/24
  62. IPN triangulation of GRB030326 (single small error box)
  63. GRB 030323: SARA Optical Observations
  64. IPN triangulation of GRB030325 (single small error box)
  65. GRB030324, optical observations
  66. GRB030324, optical observations
  67. IPN triangulation of GRB030325 (two small error boxes)
  68. GRB 030324: TAROT optical observations
  69. GRB030323: V, R, I photometry
  70. GRB 030324 (HETE #2641): Optical observations
  71. GRB030324, Optical Observations
  72. GRB030323: Upper limits from recent and historical observations.
  73. GRB030323 (=H2640): A Faint, Long GRB Localized by the HETE WXM and SXC
  74. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  75. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  76. VLT/FORS2 spectra of GRB 030323
  77. GRB030323, ROTSE-III detection of possible optical counterpart
  78. GRB030323, optical observations
  79. GRB030324, BVRcIc field photometry
  80. GRB030323, possible optical counterpart
  81. GRB030323, BVRcIc field calibration
  82. GRB 030324 optical observations
  83. GRB 030320: Optical Observations
  84. GRB 030324, optical observations
  85. IPN triangulation of GRB030320B (annulus)
  86. IPN triangulation of GRB030320 (small error box)
  87. IPN triangulation of GRB030320
  88. Possible GRB 030320 localized by INTEGRAL
  89. GRB030226, addendum to GCN 1892
  90. IPN upper limit to a GRB associated with SN2003L
  91. IPN triangulation of GRB030317 (annulus)
  92. IPN triangulation of GRB030307 (annulus)
  93. GRB 030227: Optical limit at RIKEN
  94. GRB 030226 Optical observations
  95. IPN triangulation of GRB030306 (single small error box - REVISED)
  96. GRB030226: Optical observations at Asiago
  97. IPN triangulation of GRB030306 (single small error box)
  98. IPN triangulation of GRB030306 (two small error boxes)
  99. IPN triangulation of GRB030306 (intense; annulus only so far)
  100. GRB 030226: Optical observations

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