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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"

41730 results found.

  1. SN 2003jd (SN/GRB?) -- X-ray Observations
  2. HETE Prompt GRB Spectral Analyses
  3. IPN triangulation of GRB031111 (=H2924): small error box
  4. XRF031109 (=H2919): A very long XRF localized by HETE
  5. IPN triangulation of GRB031108 (large error box)
  6. GRB031026: 1.2mm upper limit with MAMBO at the IRAM 30m
  7. GRB030929/SN2003jd association unlikely based on IPN localiztion
  8. Lulin optical follow-up observations of GRB031026
  9. SN 2003jd (SN/GRB?), Radio Observations
  10. SN 2003jd (SN/GRB?) - possible association with GRB 030929
  11. GRB 031026: Further Ic Observations
  12. GRB 031026 (=H2882): Evidence for High Redshift from Prompt
  13. Peculiar Type Ic SN 2003jd (SN/GRB?), optical spectrum
  14. IPN triangulation of GRB031024 (single error box)
  15. GRB031026 (=H2882): A Long, Hard Spectrum Burst Localized by HETE
  16. GRB 031026: Ic Observations
  17. GRB031026 : KISO optical follow-up observation
  18. GRB030329: radio observations at RT-22 (CrAO)
  19. IPN triangulation of GRB031016 (two large error boxes)
  20. HETE Prompt GRB Light Curves and Color-Color Diagrams
  21. Ongoing Bursting Activity from SGR 1806-20 detected with IBAS
  22. XRF 030824: additional observations at CFHT
  23. SGR1806-20 bursts on 031008. Helicon detection and small error box.
  24. SGR 1806-20 bursts with INTEGRAL and IBAS announcement on Soft Gamma-Ray Repeaters
  25. XRF 030723: Subaru Optical Observations
  26. IPN triangulation of GRB031004B (annulus)
  27. A burst from SGR 1806-20 detected with IBAS
  28. XRF 030824: Early follow-up observation at Kiso observatory
  29. XRF 030723: Detection of the likely host galaxy
  30. XRF030824 (=H2821): An X-Ray Flash Localized by the HETE WXM
  31. XRF030823 (=H2818): An X-Ray Flash Localized by the HETE WXM and SXC
  32. IPN triangulation of GRB030922A (large error box)
  33. IPN triangulation of GRB030921 (large error box)
  34. GRB030913: Subaru Optical Observations
  35. GRB 030913: ROTSE-3c Optical Observations
  36. GRB030913: OT's limit by MASTER
  37. GRB030913, candidate afterglow observations
  38. GRB 030913, optical candidate
  39. GRB030913: AAVSO optical observations
  40. GRB 030913, BOOTES observations
  41. GRB030913 (=H2849): Confirmation of the Flight Localization
  42. IPN triangulation of GRB030916 (possible short/hard GRB; large error box)
  43. GRB030913 (=H2849): TAROT Observations
  44. GRB030913: wide field imaging (7 sq.deg) of the error box by MASTER
  45. Magellan Observations of GRB030725 (=H2779)
  46. GRB030913 (=H2849): A GRB Possibly Localized by HETE
  47. GRB 030913: Optical limit at RIKEN
  48. XRF 020427: Gemini-South Spectroscopic Observations of the Host
  49. IBAS detection of bursts from SGR 1806-20
  50. Radio Observations of SGR1806-20
  51. IPN triangulation of GRB030830 (large error box)
  52. GRB 030824: Candidate Follow-Up
  53. INTEGRAL ToO OBSERVATIONS OF SGR1806-20: CALL FOR CORRELATED OBSERVATIONS
  54. XRF030824: Second-epoch Palomar observations
  55. XRF030824: optical observations
  56. GRB030823: optical observations
  57. XRF030824: Palomar observations
  58. GRB 030824: Candidate Afterglow (or Variable/Flare Star?)
  59. GRB030823: optical observation at Tokyo Tech
  60. RAPTOR observations of GRB030823
  61. Lulin follow-up observations of GRB030823
  62. IPN triangulation of GRB030821 (=H2814; refined error box)
  63. GRB 030821(=H2814): A Faint, Long GRB Localized by the HETE WXM and the IPN
  64. Summary of recent IPN and HETE detections of SGR bursts
  65. Clarification of GCN 2354 on SGR1806-20
  66. IPN detection of continued activity from SGR1806-20
  67. 030813 SGR event (Konus-Wind observation)
  68. SGR 1808-20 (=H2802): A Possible new SGR
  69. GRB 021206 Optical Observations
  70. XRF030723(=H2777): Chandra Fading X-ray Afterglow Confirmed
  71. IPN/HETE summary of recent bursts from SGR1806-20
  72. XRF 030723: Detection of a rebrightening in the optical afterglow
  73. GRB030725: Optical observations
  74. XRF030723, BVRcIc field photometry update
  75. GRB021206 optical counterpart upper limit
  76. XRF030723: Re-analysis of ROTSE-III early images
  77. IPN triangulation of GRB030725 (=H2779; small error box)
  78. XRF030723 (=H2777): Second Epoch Magellan Observations
  79. GRB 030725: optical observations.
  80. GRB030725, optical transient observations
  81. IPN triangulation of GRB030722 (large error box)
  82. XRF030723 Radio Observations
  83. XRF 030723: confirmation of fading optical counterpart
  84. XRF030723(=H2777): Chandra Observations
  85. XRF 030723: VLT spectra
  86. Magellan Observations of XRF030723 (=H2777)
  87. GRB030723: Upper limits from historical observations
  88. GRB030725, possible optical transient
  89. XRF030723: Palomar observations and proposed counterpart
  90. GRB030725 (=H2779): A Bright GRB Localized by HETE
  91. XRF030723: optical observations
  92. XRF030723 (= H2777): Chandra Observations Scheduled
  93. XRF030723, BVRcIc field photometry correction
  94. XRF030723, ROTSE-III Early Observations
  95. XRF030723, BVRcIc field photometry
  96. XRF030723, optical observations
  97. XRF 030723, optical observations
  98. XRF030723 (=H2777): An X-ray Flash Localized by the HETE WXM and
  99. Konus-Wind detection of the bursts from SGR1806-20 region
  100. SGR 1806-20, submm observations

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