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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"

3402 results found.

  1. XRF 050522: Continued NIR P200 Monitoring
  2. XRF050522: Near-infrared Observations
  3. XRF050509C: Chandra Afterglow Detection
  4. XRF 050509c: Swift XRT Upper Limit
  5. GRB 050520: P200 Observations
  6. GRB 050504: Swift XRT afterglow candidate has faded
  7. Refined Chandra analysis of GRB 050509b
  8. Chandra observation of GRB 050509b
  9. GRB 050502a: Swift XRT Upper Limit
  10. GRB (?) 050504: IR Observations, Intriguing Source
  11. GRB 050502: Confirmed variability of the afterglow candidate +
  12. GRB 050421: Further Analysis of IR imaging
  13. GRB 050421: IR Observations
  14. GRB050326: analysis of the XMM-Newton observation
  15. GRB050416B: IR observations
  16. GRB050416: P200 NIR Observations
  17. GRB 050408: Swift XRT measurement of possible jet break
  18. GRB 050408: Swift XRT analysis
  19. GRB050408: REM NIR and Optical observation
  20. GRB 050326 XMM-Newton observation
  21. GRB050223: analysis of the XMM-Newton observation
  22. Swift-BAT trigger 107873: No Swift XRT counterpart
  23. Swift-BAT trigger 107873 (GRB050309): possible X-ray counterparts
  24. GRB 050306: REM optical-infrared observations
  25. GRB 050126: Confirmation of the NIR afterglow candidate
  26. GRB 050219b: candidate NIR afterglow
  27. GRB 050219b: Optical and near-IR observations from LCO
  28. GRB 050126: Detection of NIR afterglow with Keck/NIRC
  29. GRB 050124: NIR afterglow confirmed with Keck/NIRC
  30. GRB 050124: NIR Candidates from Keck/NIRC
  31. GRB050117: Palomar WIRC Ks-band observations
  32. NIR Observations of GRB 041219
  33. GRB 041211: Infrared Observations
  34. GRB041015: Near-Infrared observations
  35. GRB041006: Near Infrared observations
  36. GRB040827: analysis of the XMM-Newton observation
  37. GRB 040827: 2nd epoch of Magellan K-band imaging
  38. GRB 040827: Detection of NIR afterglow
  39. GRB 040812: Second epoch CXO Observations
  40. CXO observation of GRB 040812
  41. GRB 040730, infrared observations
  42. SGR 1806-20: no IR variability of the proposed counterparts
  43. SGR 1806-20, potential NIR counterpart
  44. GRB 040511: NIR observations with REM
  45. IBAS GRB alerts 1739, 1740, 1741
  46. GRB040223: Deep NIR NTT data re-analysis
  47. GRB 040223: Deep NIR NTT observations
  48. GRB 040223: REM IJK Observations
  49. GRB 040223 XMM-Newton observation ...
  50. GRB 031203 XMM-Newton observation
  51. GRB031203: ROSAT upper limits suggest XMM-S1 source as the transient
  52. XMM-Newton Observation of GRB031203
  53. GRB 031203: Deep NIR NTT & VLT observations
  54. XMM-Newton Observation of GRB031203
  55. GRB 031203: IR NTTobservations do not confirm REM detection
  56. GRB 031203: z ~ 10 or Fragmented Dust in the Circumburst Environment?
  57. GRB 031203: IR REM Observations
  58. GRB 031203 XMM-Newton observation
  59. XRF030723: Palomar observations and proposed counterpart
  60. GRB030329: second XMM-Newton observation
  61. GRB030528(=H2724): X-ray Afterglow Identified in Second Epoch
  62. GRB 030528: Infrared Observations and the Proposed IR Counterpart
  63. GRB 030528: tentative NIR counterpart
  64. GRB 030329: Optical limit (contemporaneous photography)
  65. GRB 030429: IR photometry with IRSF/SIRIUS
  66. GRB030501: TAROT candidate afterglow present in archival images
  67. GRB 030429: confirmation of afterglow candidate
  68. GRB030418: Kiso near infrared observations
  69. GRB030329: Near Infrared Observations at Gunma
  70. GRB 030329: fading X-ray afterglow with RXTE
  71. XMM-Newton observation of GRB030227
  72. GRB 030115: Further IR observations with IRSF/SIRIUS
  73. GRB 030115: IR observations with IRSF/SIRIUS
  74. GRB 021201, optical observations
  75. GRB 021201 (short/hard), NOT observations
  76. Chandra observation of the IPN error box of GRB021201 (short/hard)
  77. Detection of activity from SGR 1900+14 with the RXTE/PCA
  78. GRB 021023: Curious K-band Source(s) Just Outside of IPN Localization
  79. GRB020812(=H2257): A Long Burst Localized by HETE in Near-Real Time
  80. SGR-like X-ray Bursts from AXP 1E 2259+586: follow-up
  81. SGR-like Bursts from the AXP 1E 2259+586
  82. GRB 020418, optical/near-IR observations
  83. GRB020531, optical observations
  84. XRF020427: Chandra Observations and Candidate X-ray Counterparts
  85. GRB 020321: Candidate X-ray Counterparts
  86. GRB 020331: Candidate Optical Afterglow
  87. GRB 020331: NIR Observations
  88. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  89. VLT observations of GRB 020124: The fading optical/near-infrared afterglow
  90. GRB 011121: NIR observations, host galaxy?
  91. GRB 011121: Detection of Bright IR Counterpart
  92. SGR 1900+14 : RXTE observations
  93. GRB 001204: Ks observations
  94. GRB 001212 possible OA in 2MASS
  95. GRB 001109: deep JHK upper limits
  96. The Likely Optical/Infrared Afterglow of GRB 001011
  97. SGR 1806-20 burst activity
  98. GRB 000418: Detection of the Host Galaxy
  99. X-ray Afterglow of GRB 000529
  100. IR observations of GRB991216

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