Hi Mark,

   Great work and thanks for the efficient and clear summary.  I’d wager that the most collegial thing to do is to alert them to your assessment of the correction factor.   That can be done in the context of your about to submit a paper comparing your results to theirs.    That would give them a chance to review and if they concur, even offer up a revision to those aspects of their paper.   That would make your job in comparing somewhat easier and less fraught with contention.  If they disagree, then you can raise the issue in your paper and let the community (and review process) decide on its own.

    I do not know Dobynde, but we have interacted with Guo who seems pretty reasonable.  I think it would be worth your reaching out to them in advance of submitting your paper just to give them advance notice and a chance to remedy things on their end. 

   I’m interested in what others think, too!

Thanks, - Harlan

_________________________________

Dr. Harlan E. Spence

Director, Institute for the Study of Earth,

   Oceans, and Space 

Professor of Physics and Astronomy

Morse Hall, Room 306 

University of New Hampshire

8 College Road

Durham, NH 03824-3525

Phone: 603-862-0322

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https://eos.unh.edu/person/harlan-spence

Twitter: @HarlanSpence2

__________________________________

From: Crater-team <crater-team-bounces@lists.sr.unh.edu> on behalf of Mark D Looper <mark.d.looper@aero.org>
Date: Tuesday, February 27, 2024 at 5:20 PM
To: crater-team@lists.sr.unh.edu <crater-team@lists.sr.unh.edu>
Cc: Timothy B Guild <timothy.b.guild@aero.org>
Subject: [Crater-team] Comparison of GLACE and REDMoon lunar albedo models

Hello—

                This took longer than I had planned, in part because I was trying to be _very_ sure that I was right.  You’ll recall that Dobynde & Guo, JGR Planets (2021), DOI: 10.1029/2021JE006930, came out with a model called REDMoon of GCR secondary particles tabulating upward and downward fluxes at and below the lunar surface.  Since GLACE focuses on upward fluxes at and above the lunar surface, they are complementary, and I thought it would be valuable to compare our results with theirs.  Since they provided tables of the values that went into the figures of their paper (thank you, AGU “Open Science” requirements!) via Zenodo, I was able to plot their upward particle fluxes in the same format as the GLACE fluxes, and I assembled the attached PPTX to compare the two.

                You may recall that in 2018 we had a joint meeting with the LRO/LEND team, and I concluded that they had left out a cosine factor in the normalization of their simulations of albedo neutrons.  The REDMoon model contains the same error, as described (and corrected) in the attached PPTX.  The comparisons actually don’t look half bad, given differences of GCR model, regolith composition, and physics list, once the corrections are applied.  However, I don’t want to catch them by surprise with a fundamental criticism of their results (especially if they end up as reviewers of our paper, right?); moreover, they are “working on building a user-friendly online platform” to make their model results broadly available, so I’d like to get them the correction before they put that into production.  What do you think would be the most collegial way to approach this?

                I’m going to put the discussion of normalization from the attached PPTX (which I lifted from a PPTX I generated after our LEND meeting over five years ago!) as an appendix to the GLACE paper; it may be the most useful piece of the whole darn thing over the long term…

Thanks—

--Mark

Mark D. Looper, PhD
Space Sciences Department
The Aerospace Corporation
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