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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').
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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

6094 results found.

  1. GRB 040812: Second epoch CXO Observations
  2. CXO observation of GRB 040812
  3. GRB 040730, infrared observations
  4. GRB 040730: Optical observations
  5. XRF 040701, optical observations
  6. SGR 1806-20: no IR variability of the proposed counterparts
  7. SGR 1806-20, potential NIR counterpart
  8. GRB 040511: NIR observations with REM
  9. GRB 040511: Optical Observations
  10. GRB040422 : I-band follow-up observation at Lulin Observatory
  11. GRB 040403: Optical Observations
  12. GRB 040323, a dark GRB ?
  13. GRB 040323: a long GRB detected with INTEGRAL
  14. GRB040223: Deep NIR NTT data re-analysis
  15. GRB040228 : KISO optical follow-up observation
  16. GRB 040223: Deep NIR NTT observations
  17. GRB 040223 : Optical observation (non-detection)
  18. GRB 040223: REM IJK Observations
  19. GRB 040223 XMM-Newton observation ...
  20. GRB 031203 XMM-Newton observation
  21. GRB031203: ROSAT upper limits suggest XMM-S1 source as the transient
  22. XMM-Newton Observation of GRB031203
  23. GRB 031203: Deep NIR NTT & VLT observations
  24. XMM-Newton Observation of GRB031203
  25. GRB 031203: IR NTTobservations do not confirm REM detection
  26. GRB031203 : Optical Observation of Lulin Observatory
  27. GRB 031203: z ~ 10 or Fragmented Dust in the Circumburst Environment?
  28. GRB 031203: IR REM Observations
  29. GRB 031203 XMM-Newton observation
  30. IPN/HETE localization of GRB031109 (=H2917; large error box)
  31. GRB 031111: Optical observations
  32. Lulin optical follow-up observations of GRB031026
  33. GRB031026 : KISO optical follow-up observation
  34. XRF 030824: additional observations at CFHT
  35. XRF 030824: observations at CFHT
  36. Magellan Observations of GRB030725 (=H2779)
  37. XRF030723: Palomar observations and proposed counterpart
  38. XRF 030723, optical observations
  39. Konus-Wind detection of the bursts from SGR1806-20 region
  40. GRB030329: second XMM-Newton observation
  41. GRB030528(=H2724): X-ray Afterglow Identified in Second Epoch
  42. GRB 030528: Infrared Observations and the Proposed IR Counterpart
  43. GRB 030528: tentative NIR counterpart
  44. GRB 030416: Optical Observations
  45. GRB 030329: Optical limit (contemporaneous photography)
  46. GRB 030429: IR photometry with IRSF/SIRIUS
  47. GRB030501: TAROT candidate afterglow present in archival images
  48. GRB 030429: confirmation of afterglow candidate
  49. GRB 030329 Oprical observations in Rozhen observatory
  50. GRB030418: Kiso near infrared observations
  51. IPN triangulation of GRB030410 (annulus)
  52. GRB030329: Near Infrared Observations at Gunma
  53. GRB 030329 Optical observations
  54. GRB 030329, BVRI photometry
  55. GRB030329: Optical observations
  56. GRB030329, optical observation
  57. GRB030329, optical observation
  58. GRB 030329, BRI photometry
  59. GRB 030329: fading X-ray afterglow with RXTE
  60. GRB 030324: Optical and NIR Observations
  61. GRB030329: R and B observations
  62. GRB 030329: OT B and R photometry, decline rate
  63. GRB030329: Upper limits from recent and historical observations.
  64. GRB 030328: optical observations
  65. GRB 030328: OT photometry
  66. GRB030323: Detection on 2003/03/24
  67. GRB 030320: Optical Observations
  68. GRB 030324, optical observations
  69. GRB030226, addendum to GCN 1892
  70. GRB 030226 Optical observations
  71. GRB 030226: Ic Observations
  72. XMM-Newton observation of GRB030227
  73. GRB 030226: Confirmed decay index
  74. GRB030217: optical observations
  75. GRB 030204: Optical Observations
  76. GRB020819: Kiso R and I band observations
  77. GRB 030204, optical observations
  78. GRB030131: Kiso optical limit for corrected position
  79. GRB030131: Kiso Observations
  80. GRB 030115: Further IR observations with IRSF/SIRIUS
  81. GRB 030115: IR observations with IRSF/SIRIUS
  82. GRB 021219: OSN optical observations
  83. GRB021211: Kiso Observations
  84. GRB021204: Kiso Observations
  85. Chandra observation of the IPN error box of GRB021201 (short/hard)
  86. GRB021113: Kiso Observations
  87. Detection of activity from SGR 1900+14 with the RXTE/PCA
  88. GRB 021023: Curious K-band Source(s) Just Outside of IPN Localization
  89. GRB021004: High-resolution optical spectroscopy
  90. XRF 020903 spectrum
  91. GRB 021004 redshift
  92. HETE fluences for GRB021004
  93. GRB 021004: Optical Observations
  94. GRB021004: Optical Spectroscopy
  95. XRF 020903: Correction to GCN 1560
  96. XRF 020903: VRI observations
  97. GRB020812: optical observations
  98. GRB 020813 multiband optical observations
  99. GRB/XRF 020427, detection of an underlying system with the VLT
  100. SGR-like X-ray Bursts from AXP 1E 2259+586: follow-up

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