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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').

10043 results found.

  1. IPN triangulation of GRB030301 (annulus)
  2. 030302: NOT A GRB
  3. 030228: NOT A GRB
  4. GRB 030226: R band polarimetric observations
  5. GRB 20030226: Upper limits from recent and historical observations
  6. GRB030227 - faint tentative OT candidate
  7. XMM-Newton observation of GRB030227
  8. GRB030226: ESI spectroscopy
  9. GRB030226 (=U10893): A Long GRB Localized by the HETE WXM and SXC
  10. GRB030226: optical observations and refined redshift
  11. GRB 030226 Optical Spectra and R,I,z' Imaging
  12. GRB030226: Candidate optical afterglow
  13. IPN triangulation of GRB030220 (annulus)
  14. IPN triangulation of GRB030217 (small error box)
  15. IPN triangulation of GRB030215C (annulus)
  16. IPN triangulation of GRB030217 (annulus)
  17. IPN triangulation of GRB030215A and GRB030215B (annuli)
  18. IPN triangulation of GRB030204 (small error box)
  19. IPN triangulation of GRB030127 (annulus)
  20. GRB 030115: Further IR observations with IRSF/SIRIUS
  21. GRB 030115: IR observations with IRSF/SIRIUS
  22. GRB030115: R-band counterpart of IR candidate
  23. GRB 021211: R-band observations at late-time
  24. IPN triangulation of GRB030115B (small error box)
  25. GRB030115 (=H2533): A Long GRB Localized by the HETE WXM and SXC
  26. IPN triangulation of GRB030115B (annulus)
  27. GRB030115: R-band observations at Asiago
  28. IPN triangulation of GRB030101 (two large error boxes)
  29. Probable GRB in INTEGRAL SPI-ACS
  30. GRB021219, optical observations
  31. IPN triangulation of GRB021214 (annulus)
  32. GRB 021211, optical observations
  33. GRB 021211, optical observations
  34. GRB021211 - Upper limits from recent and historical observations
  35. GRB021211 (=H2493): A Bright, Long GRB Localized by HETE-2 in Near-Real Time
  36. HETE 2493: Optical observations
  37. IPN triangulation of GRB021201 (short/hard burst, small error box)
  38. GRB021125 refined position
  39. IPN triangulation of GRB021125B (two large error boxes)
  40. GRB021113, SPI ACS observation
  41. GRB021113: optical observations at Bisei
  42. GRB021112: Optical Observations
  43. IPN triangulation of GRB021113 (=H2449; annulus)
  44. GRB021113 (=H2449): A Long GRB Localized by HETE
  45. GRB021112 (=H2448): A Long GRB Localized by HETE
  46. IPN triangulation of GRB021104 (annulus)
  47. GRB021104(=H2434): A Long, X-Ray-Rich GRB Localized by HETE
  48. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  49. GRB021104: Candidate present in DSS
  50. IPN triangulation of GRB021025 (portion of annulus)
  51. IPN triangulation of GRB021025 (annulus)
  52. IPN triangulation of GRB021023 (small error boc)
  53. IPN triangulation of GRB021020 (smaller error box)
  54. GRB021021(=XRF 021021): An X-ray Flash Localized by HETE
  55. IPN triangulation of GRB021020
  56. GRB 021004: VRI observations at TNG: possible break
  57. GRB021016(=H2397): A Long GRB Localized by HETE
  58. IPN triangulation of GRB021016 (small error box)
  59. IPN triangulation of GRB021014 (large error box)
  60. GRB021004: High-resolution optical spectroscopy
  61. GRB 021004: Optical/NIR Observations
  62. GRB 021004: Additional V-band Polarimetric Observations
  63. GRB021004: optical observation
  64. GRB 021004: WC wind?
  65. IPN triangulation of GRB021007 (annulus)
  66. XRF 020903 spectrum
  67. GRB021004: optical observations and predicted break time
  68. GRB021004: restart of optical decay
  69. GRB 021004: Optical Decay
  70. HETE fluences for GRB021004
  71. GRB 021004: V-band Polarimetric Observations
  72. GRB021004: Update Bisei photometric data
  73. GRB 021004: Optical Decay
  74. GRB021004, Optical Observations
  75. GRB021004: Upper limits from recent and historical observations
  76. GRB021004(=H2380): Revised Localization with HETE Soft X-ray
  77. GRB021004(=H2380): A Long GRB Localized by HETE in Near-Real Time
  78. XRF020903: TNG and Asiago photometry
  79. XRF 020903: Correction to GCN 1560
  80. XRF 020903: VRI observations
  81. XRF 020903: Supernova
  82. Single IPN error box for GRB020904
  83. IPN triangulation of GRB020904
  84. GRB020903(=H2314): An X-Ray Flash Localized by HETE
  85. GRB020819(=H2275): Revised Localization with HETE Soft X-ray
  86. SGR1900+14 burst localized by HETE
  87. GRB020813: High-resolution optical spectroscopy
  88. Second epoch K band imaging of GRB 020819
  89. K band observation of GRB 020819
  90. GRB020819(=H2275): A Long Burst Localized by the HETE WXM and SXC
  91. IPN triangulation of GRB020819 (HETE 2275)
  92. GRB 020813: addendum to GCN 1498
  93. GRB020813: V-band decay slope
  94. Polarimetry of GRB020813: evidence for variability
  95. GRB020813: High-Resolution Optical Observations
  96. GRB020813(=H2262): Revised Localization with HETE SXC
  97. GRB020813, optical observations
  98. IPN error box for GRB020813
  99. IPN triangulation of GRB020813
  100. GRB020813(=H2262): A Long, Bright Burst Localized by HETE in Near-Real Time

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