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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').

18685 results found.

  1. GRB030329 - Light curve flattening
  2. GRB 030324, optical search
  3. GRB 030329, optical observations
  4. GRB030328: X-ray Fading and Spectrum Measured with Chandra
  5. GRB030329a: detection by Konus-Wind
  6. GRB030329b: detection by Konus-Wind and Helicon-CoronasF
  7. GRB 030329: Light curve observed during the change of its slope.
  8. GRB030329, BVRcIc field photometry
  9. GRB030329, SPM optical observations
  10. GRB030329 optical observations
  11. GRB 030329: Optical pre-Imaging
  12. GRB 030329: Upper limit from 5.6 hours before trigger
  13. GRB030328: X-ray Afterglow Observed with Chandra
  14. GRB 030329, R-band observations
  15. GRB030329: Upper limits from recent and historical observations.
  16. GRB 030329: Optical Afterglow Observations
  17. GRB 030328: optical observations
  18. GRB 030329: Optical afterglow fading
  19. GRB 030329: Optical afterglow candidate
  20. GRB 030328: OT photometry
  21. GRB030328: optical photometry at the TNG
  22. GRB030328 (=H2650): A Long, Bright GRB Localized by the HETE WXM and SXC
  23. GRB 030328: Optical observations
  24. GRB030324 optical observation
  25. GRB030131, BVRcIc field photometry
  26. Possible GRB030323 localized by INTEGRAL
  27. GRB030323: Detection on 2003/03/24
  28. GRB030324, optical observations
  29. GRB030323: V, R, I photometry
  30. GRB030323 (=H2640): A Faint, Long GRB Localized by the HETE WXM and SXC
  31. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  32. VLT/FORS2 spectra of GRB 030323
  33. GRB030323, ROTSE-III detection of possible optical counterpart
  34. GRB030323, optical observations
  35. GRB030324, BVRcIc field photometry
  36. GRB030323, BVRcIc field calibration
  37. Possible GRB 030320 localized by INTEGRAL
  38. GRB030226, BVRc observations
  39. Chandra detection of the X-ray afterglow of GRB 030226
  40. GRB 030226: Ic Observations
  41. GRB030227: Kiso optical upper limit
  42. GRB030227, BVRcIc field photometry
  43. GRB030226, BVRcIc field calibration
  44. GRB 030228, optical observations
  45. GRB 030227: Confirmed Optical Afterglow (S1-A)
  46. GRB 030227: fading of candidate optical afterglow 'S1-A'
  47. GRB030227:Optical observations
  48. GRB 030227, possible optical counterpart of XMM-Newton source
  49. GRB030227: Kiso optical observations
  50. GRB 030227: Kyoto optical observation
  51. GRB030227 localized by INTEGRAL
  52. Possible break in the GRB 030226 light curve
  53. GRB030226: ESI spectroscopy
  54. GRB030226 (=U10893): A Long GRB Localized by the HETE WXM and SXC
  55. GRB 030226 simultaneous optical observations
  56. GRB 030226, optical observations
  57. GRB030226: Optical decay index
  58. GRB 030217: Optical Observations at 4, 5, and 6 Days
  59. GRB 030131: marginal optical detection
  60. GRB 030204: Optical Observations
  61. GRB030204 field photometry
  62. GRB020819: Kiso R and I band observations
  63. GRB030131: Candidate Optical Afterglow
  64. GRB 030131, optical observations
  65. GRB 030131: afterglow candidate
  66. GRB 030115, late-time optical observations
  67. GRB030131: corrected INTEGRAL position
  68. GRB 020819: Host galaxy at Radio Position
  69. IPN triangulation of GRB030131
  70. GRB 030131 optical observations
  71. GRB030131: refined position
  72. GRB 030131 optical observations
  73. A long GRB detected by INTEGRAL
  74. GRB030115: 1.2 mm upper limits with MAMBO @ IRAM 30m
  75. GRB 030115, simultaneous observations by BOOTES-1
  76. GRB 030115: IR observations with IRSF/SIRIUS
  77. GRB030115, afterglow candidate
  78. GRB030115: Optical Observations, Swiss Telescope at La Silla (ESO, Chile)
  79. GRB 030115 : Possible IR counterpart
  80. Distribution of INTEGRAL SPI-ACS triggers for GRB bursts
  81. GRB 030115: APO Optical Observations
  82. IPN triangulation of GRB030102 (annulus)
  83. VLT spectroscopy of the probable host of GRB 021211
  84. GRB 021211: Probable Host and Underlying Supernova
  85. GRB 021112: Evidence for Another Dark Optical Afterglow
  86. GRB 021219: OSN optical observations
  87. GRB021219, optical observations
  88. GRB021219, optical observation by MASTER
  89. GRB021219: a long GRB localized by INTEGRAL
  90. GRB021211: APO optical observations
  91. IPN detection of continued activity from SGR1806-20
  92. XRF 020903 : HST observations
  93. GRB 021201: Optical Observations
  94. GRB 021211: CTIO observations
  95. GRB 021211: early break in light curve
  96. GRB021211, BVRI field photometry
  97. GRB021211: Optical observations in CrAO
  98. GRB 021211, optical observations
  99. GRB021211: Kiso Observations
  100. GRB 021201, optical observations

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