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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"

23410 results found.

  1. OT GRB 030329: early spectrum
  2. GRB030324: Candidate Optical Afterglow
  3. IPN triangulation of GRB030414 (small error box)
  4. GRB 030413: Optical Observations
  5. IPN triangulation of GRB030413 (small error box)
  6. IPN triangulation of GRB030410 (annulus)
  7. Superluminal motion in GRB 030329 (Correction)
  8. Superluminal motion in GRB 030329
  9. GRB 030329 and SN 2003dh
  10. GRB030329, optical position
  11. IPN triangulation of GRB030406 (small error box)
  12. IPN triangulation of GRB050403 (small error box)
  13. IPN triangulation of GRB030403 (annulus)
  14. GRB 030329: BVRI photometry at Asiago
  15. GRB 030329, light curve flattens
  16. GRB 030329: VLT V-band photometry
  17. Kiso observation of the GRB030329 at April 6
  18. GRB030328, UBVRcIc field photometry
  19. GRB 030329 Optical observations
  20. GRB030329: Kiso B and R band observations
  21. GRB030328: R upper limit after 6 hours by MASTER
  22. GRB 030329, BVRI photometry
  23. SDSS 0.5m PT observations of GRB030329 (correction)
  24. SDSS 0.5m PT observations of GRB030329
  25. GRB 030329, nearby galaxies
  26. GRB030329: final R-band light curve by MASTER
  27. GRB030329 Radio 23/43/90 GHz observations at Nobeyama
  28. GRB030329, optical observation
  29. GRB030329, new UBVRcIc field photometry
  30. GRB 030329, light curve and SN prediction
  31. GRB030328: Full Observation, X-ray Fading and Spectrum Measured
  32. GRB030329: Optical observations at Teramo
  33. GRB 030329: Radio observations at GMRT
  34. GRB 030329: Additional Mt. Laguna Optical Observations
  35. GRB 030329: Observations with ANDICAM
  36. triangulation of GRB 030331 (single error box)
  37. AAVSO V & R observations of GRB030329
  38. IPN triangulation of GRB030331 (annulus)
  39. GRB 030329: optical observations
  40. IPN triangulation of GRB030329b (large error box)
  41. Photometry of GRB030329 - Constant OT Magnitude
  42. GRB 030324: Optical and NIR Observations
  43. GRB030329: R band light curve by MASTER
  44. GRB030329 - Light curve flattening
  45. GRB 030324, optical search
  46. GRB030329 - near contemporaneous optical limits from CONCAM
  47. GRB 030329, optical observations
  48. GRB030328: X-ray Fading and Spectrum Measured with Chandra
  49. GRB030329b: detection by Konus-Wind and Helicon-CoronasF
  50. GRB030329, BVRcIc field photometry
  51. GRB030329, SPM optical observations
  52. GRB030329 optical observations
  53. GRB 030329: Optical pre-Imaging
  54. GRB 030329: Upper limit from 5.6 hours before trigger
  55. GRB030328: X-ray Afterglow Observed with Chandra
  56. GRB 030329, R-band observations
  57. GRB030329: Upper limits from recent and historical observations.
  58. GRB 030329: Optical Afterglow Observations
  59. GRB 030328: optical observations
  60. GRB 030329: Optical afterglow fading
  61. GRB 030328: OT photometry
  62. GRB030328: optical photometry at the TNG
  63. GRB 030328: Optical observations
  64. GRB030324 optical observation
  65. GRB030131, BVRcIc field photometry
  66. Possible GRB030323 localized by INTEGRAL
  67. GRB030323: Detection on 2003/03/24
  68. IPN triangulation of GRB030326 (single small error box)
  69. GRB030324, optical observations
  70. IPN triangulation of GRB030325 (two small error boxes)
  71. GRB 030324: TAROT optical observations
  72. GRB030323: V, R, I photometry
  73. GRB030323: Upper limits from recent and historical observations.
  74. VLT/FORS2 spectra of GRB 030323
  75. GRB030323, optical observations
  76. GRB030324, BVRcIc field photometry
  77. GRB030323, BVRcIc field calibration
  78. GRB 030324 optical observations
  79. IPN triangulation of GRB030320B (annulus)
  80. IPN triangulation of GRB030320 (small error box)
  81. Possible GRB 030320 localized by INTEGRAL
  82. IPN triangulation of GRB030317 (annulus)
  83. IPN triangulation of GRB030307 (annulus)
  84. GRB 030227: Optical limit at RIKEN
  85. GRB 030226 Optical observations
  86. IPN triangulation of GRB030306 (single small error box - REVISED)
  87. IPN triangulation of GRB030306 (single small error box)
  88. IPN triangulation of GRB030306 (two small error boxes)
  89. IPN triangulation of GRB030304 (annulus)
  90. GRB 030227: Optical observations
  91. GRB030226, BVRc observations
  92. Chandra detection of the X-ray afterglow of GRB 030226
  93. GRB 030226, further optical/NIR imaging
  94. GRB030227: Kiso optical upper limit
  95. IPN triangulation of GRB030301 (annulus)
  96. IPN triangulation of GRB030228 (annulus)
  97. GRB030227, BVRcIc field photometry
  98. GRB030226, BVRcIc field calibration
  99. GRB 030228, optical observations
  100. GRB 030227: Confirmed Optical Afterglow (S1-A)

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