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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"

3079 results found.

  1. GRB 050306: REM optical-infrared observations
  2. GRB 050126: Confirmation of the NIR afterglow candidate
  3. GRB 050219b: candidate NIR afterglow
  4. GRB 050219b: Optical and near-IR observations from LCO
  5. GRB 050126: Detection of NIR afterglow with Keck/NIRC
  6. GRB 050124: NIR afterglow confirmed with Keck/NIRC
  7. GRB 050124: NIR Candidates from Keck/NIRC
  8. GRB050117: Palomar WIRC Ks-band observations
  9. NIR Observations of GRB 041219
  10. GRB 041211: Infrared Observations
  11. GRB041015: Near-Infrared observations
  12. GRB041006: Near Infrared observations
  13. GRB040827: analysis of the XMM-Newton observation
  14. GRB 040827: 2nd epoch of Magellan K-band imaging
  15. GRB 040827: Detection of NIR afterglow
  16. GRB 040812: Second epoch CXO Observations
  17. CXO observation of GRB 040812
  18. GRB 040730, infrared observations
  19. SGR 1806-20: no IR variability of the proposed counterparts
  20. SGR 1806-20, potential NIR counterpart
  21. GRB 040511: NIR observations with REM
  22. IBAS GRB alerts 1739, 1740, 1741
  23. GRB040223: Deep NIR NTT data re-analysis
  24. GRB 040223: Deep NIR NTT observations
  25. GRB 040223: REM IJK Observations
  26. GRB 040223 XMM-Newton observation ...
  27. GRB 031203 XMM-Newton observation
  28. GRB031203: ROSAT upper limits suggest XMM-S1 source as the transient
  29. XMM-Newton Observation of GRB031203
  30. GRB 031203: Deep NIR NTT & VLT observations
  31. XMM-Newton Observation of GRB031203
  32. GRB 031203: IR NTTobservations do not confirm REM detection
  33. GRB 031203: z ~ 10 or Fragmented Dust in the Circumburst Environment?
  34. GRB 031203: IR REM Observations
  35. GRB 031203 XMM-Newton observation
  36. XRF030723: Palomar observations and proposed counterpart
  37. GRB030329: second XMM-Newton observation
  38. GRB030528(=H2724): X-ray Afterglow Identified in Second Epoch
  39. GRB 030528: Infrared Observations and the Proposed IR Counterpart
  40. GRB 030528: tentative NIR counterpart
  41. GRB 030329: Optical limit (contemporaneous photography)
  42. GRB 030429: IR photometry with IRSF/SIRIUS
  43. GRB030501: TAROT candidate afterglow present in archival images
  44. GRB 030429: confirmation of afterglow candidate
  45. GRB030418: Kiso near infrared observations
  46. GRB030329: Near Infrared Observations at Gunma
  47. GRB 030329: fading X-ray afterglow with RXTE
  48. XMM-Newton observation of GRB030227
  49. GRB 030115: Further IR observations with IRSF/SIRIUS
  50. GRB 030115: IR observations with IRSF/SIRIUS
  51. GRB 021201, optical observations
  52. GRB 021201 (short/hard), NOT observations
  53. Chandra observation of the IPN error box of GRB021201 (short/hard)
  54. Detection of activity from SGR 1900+14 with the RXTE/PCA
  55. GRB 021023: Curious K-band Source(s) Just Outside of IPN Localization
  56. GRB020812(=H2257): A Long Burst Localized by HETE in Near-Real Time
  57. SGR-like X-ray Bursts from AXP 1E 2259+586: follow-up
  58. SGR-like Bursts from the AXP 1E 2259+586
  59. GRB 020418, optical/near-IR observations
  60. GRB020531, optical observations
  61. XRF020427: Chandra Observations and Candidate X-ray Counterparts
  62. GRB 020321: Candidate X-ray Counterparts
  63. GRB 020331: Candidate Optical Afterglow
  64. GRB 020331: NIR Observations
  65. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  66. VLT observations of GRB 020124: The fading optical/near-infrared afterglow
  67. GRB 011121: NIR observations, host galaxy?
  68. GRB 011121: Detection of Bright IR Counterpart
  69. SGR 1900+14 : RXTE observations
  70. GRB 001204: Ks observations
  71. GRB 001212 possible OA in 2MASS
  72. GRB 001109: deep JHK upper limits
  73. The Likely Optical/Infrared Afterglow of GRB 001011
  74. SGR 1806-20 burst activity
  75. GRB 000418: Detection of the Host Galaxy
  76. X-ray Afterglow of GRB 000529
  77. IR observations of GRB991216
  78. BeppoSAX NFI Observation of GRB991106
  79. GRB980703: Radio transient

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