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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"

24361 results found.

  1. XRF030723: Re-analysis of ROTSE-III early images
  2. XRF030723 (=H2777): Second Epoch Magellan Observations
  3. GRB030725, possible optical transient
  4. XRF030723: Palomar observations and proposed counterpart
  5. GRB030725 (=H2779): A Bright GRB Localized by HETE
  6. XRF030723, BVRcIc field photometry correction
  7. XRF030723, ROTSE-III Early Observations
  8. XRF030723 (=H2777): An X-ray Flash Localized by the HETE WXM and
  9. Konus-Wind detection of the bursts from SGR1806-20 region
  10. IBAS GRB Alerts 969 970
  11. SGR 1806-20, submm observations
  12. H2768, H2770, and H2771: Three Bursts from SGR1806-20
  13. IPN triangulation of GRB030717 (annulus)
  14. 030716 NOT a GRB
  15. 030629 NOT a real GRB
  16. GRB030329: second XMM-Newton observation
  17. GRB030418: R optical observations
  18. GRB 030528: tentative NIR counterpart
  19. GRB030329, further radio observations at GMRT
  20. MASTER: optical observation GRB030601
  21. GRB030528(=H2724): Revised SXC Localization
  22. GRB 030329/SN 2003dh: Jitter Episode
  23. GRB 030528, Teramo optical observation
  24. GRB030528 (H2724): A long GRB localized by HETE
  25. GRB 030329: Correction to GCN 2254
  26. GRB 030329: Optical Observations
  27. GRB 030416: Optical Observations
  28. GRB030329, Optical observations
  29. GRB 030329/SN 2003dh: Possible increase in brightness
  30. GRB 021004: HST observations
  31. GRB030519B (=H2716): Peak Fluxes, Fluences, and Energy Spectrum
  32. GRB030519B (=H2716): A Long, Bright GRB Localized by the HETE WXM
  33. GRB 030329: Optical limit (contemporaneous imaging)
  34. GRB030329, BVRI photometry
  35. GRB 030329: Optical limit (contemporaneous photography)
  36. GRB030429 (=H2695): A Long GRB Localized by the HETE WXM and SXC
  37. GRB030418 (=H2686): A Long, X-Ray-Rich GRB Localized by the HETE WXM
  38. XRF030416 (=U10897): An X-Ray Flash Localized by the HETE WXM
  39. GRB 030329: all-sky CCD images by K. Shiokawa immediately after the burst
  40. GRB030501, optical observation
  41. GRB030501 triangulation (correction to GCN 2194)
  42. GRB 030329 Optical Observations
  43. GRB030328, optical observation
  44. GRB 030329, BVRI photometry
  45. IPN triangulation of GRB030501 (IBIS event; annulus)
  46. GRB030501 localized by INTEGRAL
  47. IPN triangulation of GRB030428 (two large error boxes)
  48. GRB 030429: ROTSE-III observations
  49. GRB030329 observed as a sudden ionospheric disturbance (SID)
  50. IPN triangulation of GRB030426 (annulus)
  51. GRB 030329: optical spectropolarimetry at VLT
  52. GRB030329, optical observation
  53. MASTER:optical observations GRB030416
  54. ROTSE-III prompt optical detections of GRB 030418
  55. GRB 030418: Optical afterglow candidate
  56. GRB030329: Optical Observations
  57. GRB030329, UBVRI polarimetry, R-polarization
  58. GRB 030329: SARA Optical Observations
  59. OT GRB 030329: early spectrum
  60. GRB030324: Candidate Optical Afterglow
  61. Superluminal motion in GRB 030329 (Correction)
  62. Superluminal motion in GRB 030329
  63. GRB 030329 and SN 2003dh
  64. GRB 030329 VLBA Observations
  65. GRB030328, UBVRcIc field photometry
  66. GRB 030329: possible color change
  67. GRB030329: RTT150 optical observations
  68. GRB030329: Kiso B and R band observations
  69. GRB030329: More AAVSO VR obs
  70. GRB 030329: SARA Optical Observations
  71. GRB 030329: SARA Optical Observations
  72. GRB030329: Optical observations
  73. GRB030329, cessation of fading
  74. GRB 030329: SARA Optical Observations
  75. GRB030329, optical observation
  76. GRB030329, optical observation
  77. GRB030329, new UBVRcIc field photometry
  78. GRB 030329, light curve and SN prediction
  79. GRB030328: Full Observation, X-ray Fading and Spectrum Measured
  80. GRB030329: Optical observations at Teramo
  81. GRB 030329: Radio observations at GMRT
  82. Further AAVSO V,B,R observations of GRB030329
  83. GRB 030329: Observations with ANDICAM
  84. GRB030329: Optical observations
  85. GRB030329 - OT rebrightens
  86. AAVSO V & R observations of GRB030329
  87. GRB 030329: optical observations
  88. GRB030329: Optical observations
  89. Photometry of GRB030329 - Constant OT Magnitude
  90. GRB030329: Near Infrared Observations
  91. 030331 NOT A GRB
  92. GRB 030324: Optical and NIR Observations
  93. GRB030329: R band light curve by MASTER
  94. GRB 030324, optical search
  95. GRB030329 - near contemporaneous optical limits from CONCAM
  96. GRB030329: R and B observations
  97. GRB030329: Optical observations
  98. GRB030328: X-ray Fading and Spectrum Measured with Chandra
  99. GRB030329a: detection by Konus-Wind
  100. GRB030329b: detection by Konus-Wind and Helicon-CoronasF

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