GRB 250129A¶

Photometry and validation¶

Team:

Prompt¶

X-ray¶

Analysis: Dahlia, Thomas Hussenot, Mona (GRANDMA)
Review: Magui (Colibri)--Analysis; Sarah--Text
Status: up to 27.09.2025

Lightcurve points have been finalized:

• Points are binned with non-continuous, manually defined time indices to group specific points in clusters with the purpose of decreasing uncertainty and acquiring a smoother cadence.
• Lightcurve provided at 10keV and 2keV Flux density (uJy) and AB magnitudes.
• 2keV has been included in the main lightcurve figure and used for the NMMA and Refreshed Shocks Shell Collisions analyses while 2 and 10 keV where used for MCMC analysis.

Review by Magui:

• Curve consistent with Swift XRT
• Explain further in the text the specifics of the contiguous segments "If a unique time bin cannot be defined, better to specify each time bin used".

Status of the text:
Text explaining the light curve and analysis method has been completed.

Text for the spectral fitting has been written, covering the analysis done on the three sources within T-T0 = 1 day. The fitting was done for the photon index and normalization factor, where the photon index was compatible within errors between the sources and relatively unchanging. Based on comments by Antonio and Tanomy, the photon index will not be varied

Further investigation has been done for the second spectral source which covers the first flare to test for any evolution by comparing the spectral fit during the rise VS decay phase.

Text has been reviewed and some details of the analysis has been moved into the appendix to allow the paper to focus on the main analyses and results.

UV¶

Analysis: Mona (GRANDMA) and Sam (Swift)
Review: Sarah
Status: up to 27.09.2025
The analysis of the UV data has been independently conducted by Mona Molham (GRANDMA side) and Sam Oates (SWIFT side, expert recommended by Phil Evans and Antonio de Ugarte Postigo). Sam Oates provided a detailed dataset that included individual data points, with detections and upper limits. In her method, a detection can include measures with errors that correspond to an SNR up to 1.

Mona and Dahlia correspond with Sam, and Mona follows Sam's method, in addition to stacking the data.

Results from both analysts were uploaded to Skyportal: Sam’s independently, and Mona’s on May 1st and May 19th. The results were then reviewed by Sarah Antier.

Sarah's review process involved two main checks:

a) Cross-validation of Analyses: She assessed the consistency between Mona’s and Sam’s datasets, primarily by ensuring the compatibility of their error bars.

b) Cross-check with Optical Data: She examined whether any significant features (e.g., bumps in the light curve) seen in the UV also appeared in the optical bands.

As part of her quality control, Sarah excluded all points with an SNR below 3. She requested Mona to re-stack them to potentially raise the SNR above this threshold when the data could be grouped/clustered appropriately by time, while not sacrificing time resolution in the log-scale. This step was done for the affected UV filters: UV white, B, UVW1, UVW2, UVM1, and UVM2.

Text summarizing the UVW1 data was written by Mona under the instructions of Dahlia. Text is complete.

Optical¶

Analysis: Dahlia, Sergey (GRANDMA), with the help of Francesco for Colibri
Review: Sarah
Status: up to 27.09.2025

The Review was performed by Sarah. Detailed status can be found in the dedicated page.
Lightcurve has been COMPLETE + VALIDATED and the final version has been provided to the GRANDMA/NMMA team and the UNAM team.

Text has been reviewed and some details of the analysis has been moved into the appendix to allow the paper to focus on the main analyses and results.

Review photometry

Extinction¶

Analysis: Dahlia
Reviewer: M. Pillas

• GRB coordinates: correct
• Code: correct
• Reproduction of the results: done
• diff MWcorrected_GRB250129A_review.csv MWcorrected_GRB250129A.csv showed no difference.

The extinction correction has been checked and is validated.

Review on the article