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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').

18670 results found.

  1. GRB021113: optical observations at Bisei
  2. GRB 021113: Evidence for a Dark Optical Afterglow
  3. GRB021112, BVRI field photometry
  4. GRB 021112: Variable Source in R-band search
  5. GRB021112: Optical Observations
  6. GRB 021113: Optical observations
  7. GRB 021112: RAPTOR Observations
  8. GRB021113 (=H2449): A Long GRB Localized by HETE
  9. GRB 021016: Optical Observations
  10. GRB021104(=H2434): A Long, X-Ray-Rich GRB Localized by HETE
  11. SGR1900+14 activity, November 2-4, 2002
  12. GRB021104: optical observations
  13. Detection of activity from SGR 1900+14 with the RXTE/PCA
  14. GRB 021004: optical observations
  15. GRB 021008, radio observations
  16. GRB 021008, optical observations
  17. IPN triangulation of GRB021014 (large error box)
  18. IPN triangulation of GRB021013 (two small error boxes)
  19. XRF 020903: flattening of the optical light curve.
  20. GRB021004, UBVRcIc field photometry update
  21. IPN triangulation of GRB021008 (two small error boxes)
  22. GRB021004 Chandra HETG Observations
  23. GRB 021004: Optical/NIR Observations
  24. GRB 021004: Additional V-band Polarimetric Observations
  25. GRB021004: optical observation
  26. GRB 021004: Host Galaxy Star Formation Rate
  27. GRB 021004: WC wind?
  28. IPN triangulation of GRB021008
  29. GRB 021004: Optical observations, AUDE network
  30. IPN triangulation of GRB021007 (annulus)
  31. GRB021004: BVRc photometry
  32. GRB021004 radio observation
  33. GRB 021004 continued IR fading
  34. GRB 021004: Optical Photometry at 2.5 Days
  35. GRB 021004: polarimetric observations
  36. GRB 021004: V-band Polarimetric Observations
  37. GRB021004: Update Bisei photometric data
  38. GRB 021004 radio observation
  39. GRB 021004: Optical Observations
  40. GRB021004: continued fading
  41. GRB 021004: Optical Photometry at 1.5 Days
  42. GRB021004, Optical Observations
  43. GRB021004, BVRcIc field photometry
  44. GRB021004: Optical Spectroscopy
  45. GRB 021004: Optical Observations
  46. GRB 021004, SPM optical observations
  47. GRB 021004, optical observations
  48. GRB 021004 radio search
  49. GRB021004: Upper limits from recent and historical observations
  50. XRF020903, BVRI field photometry
  51. XRF020903: TNG and Asiago photometry
  52. XRF 020903: Correction to GCN 1560
  53. XRF 020903: VRI observations
  54. XRF 020903: R band observations
  55. IPN triangulation of GRB020923 (two error boxes)
  56. IPN triangulation of GRB020914B
  57. IPN annulus for GRB020914B
  58. IPN triangulation of GRB020911 (2 large error boxes)
  59. GRB 020305: HST/STIS observations
  60. Single IPN error box for GRB020904
  61. XRF 020903: optical observation at Kyoto
  62. GRB020322 : HST/STIS observations
  63. XRF 020903: Optical observations
  64. IPN triangulation of GRB020904
  65. IPN detection of a burst from SGR1900+14
  66. INTEGRAL GRBs added to GCN
  67. GRB020812: negative optical observations
  68. GRB 020812: optical observation at Kyoto University
  69. Second epoch K band imaging of GRB 020819
  70. GRB020813, Baade 6.5m data now available
  71. GRB 020813 : HST observations
  72. GRB 020812: early time optical observation at Ouda Station
  73. GRB020813: Magellan BVRI Photometry
  74. GRB 020819: Optical observations
  75. GRB020813: optical and NIR observations
  76. GRB020813: Fading X-ray Afterglow Observed with Chandra
  77. GRB020813, UBVRI field calibration
  78. Polarimetry of GRB020813: evidence for variability
  79. GRB020812: optical observations
  80. GRB020813: High-Resolution Optical Observations
  81. GRB 020812: optical observation at Bisei
  82. GRB020812: optical observations
  83. GRB020813, optical observations
  84. GRB020813, astrometric position
  85. GRB 020812 optical observation
  86. GRB 020714, optical observations
  87. GRB020801: Imaging of Suggested OT Counterpart at the Magellan
  88. HST Imaging of the Host of GRB 011121
  89. GRB020801, optical afterglow candidate
  90. GRB020331: Late-time Optical Light Curve (re-submission)
  91. GRB020331: Late-time Optical Light Curve
  92. IPN triangulation of GRB020714
  93. IPN triangulation of GRB150702
  94. GRB 020410: Discovery of Probable OT by HST
  95. IPN triangulation of GRB020708
  96. IPN triangulation of GRB020708
  97. Correction to IPN error box for GRB020706
  98. IPN triangulation of GRB020706
  99. GRB 020705: Optical observations
  100. GRB 020625: Optical observations

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