# Uncertainty in mean $X_{\rm max}$ from diffractive dissociation estimated using measurements of accelerator experiments

### Submission summary

 As Contributors: Ken Ohashi Arxiv Link: https://arxiv.org/abs/2208.04645v2 (pdf) Date submitted: 2022-09-27 14:12 Submitted by: Ohashi, Ken Submitted to: SciPost Physics Proceedings Proceedings issue: 21st International Symposium on Very High Energy Cosmic Ray Interactions (ISVHECRI 2022) Academic field: Physics Specialties: Gravitation, Cosmology and Astroparticle Physics Approach: Experimental

### Abstract

Mass composition is important for understanding the origin of ultra-high-energy cosmic rays. However, interpretation of mass composition from air shower experiments is challenging, owing to significant uncertainty in hadronic interaction models adopted in air shower simulation. A particular source of uncertainty is diffractive dissociation, as its measurements in accelerator experiments demonstrated significant systematic uncertainty. In this research, we estimate the uncertainty in $\langle X_{\rm max}\rangle$ from the uncertainty of the measurement of diffractive dissociation by the ALICE experiment. The maximum uncertainty size of the entire air shower was estimated to be $^{+4.0}_{-5.6}~\mathrm{g/cm^2}$ for air showers induced by $10^{17}$~eV proton, which is not negligible in the uncertainty of $\langle X_{\rm max}\rangle$ predictions.

###### Current status:
Has been resubmitted

We revised manuscripts considering all comments by the referee.

### List of changes

Update descriptions in section 4 to avoid confusion.
Add one reference and apply several modifications suggested by the referee.

### Submission & Refereeing History

Resubmission 2208.04645v3 on 6 October 2022

Resubmission 2208.04645v2 on 27 September 2022
Submission 2208.04645v1 on 10 August 2022

## Reports on this Submission

### Report

This draft has been improved and the paper should be publlished in the poceeding, but after a few changes of the text.

### Requested changes

(1) page 3 just after the chapter 4, Analysis method. A few lines should be written correctly. for example,
In this work, we focus on the effects of the first intercation of air showers. We categorize simulated air showers by collision types at the first intercation and the mean value was calculated. The mean value of Xmax < >, of each categorized samples was calculated as following definition of f and Eq.(1)where i..samples. By changing the fraction f in Eq.1, we have estimated the effect of each fraction.
(2) page 5 line 8 from the top. Total uncertainty for the first intercation considering the result of the ALICE experiment was .. calculated from the 1.6g/cm2 difference bewteen the two models and the uncertainty in the two....
(3) page 5 line 12 from the top. You may need the reference where you have provided the number 2.4.
(4) page 5 line 15. As the difference --> Although the difference

• validity: good
• significance: high
• originality: ok
• clarity: low
• formatting: acceptable
• grammar: acceptable