ICRC 2021

Jul 12 – 23, 2021
Online
Europe/Berlin timezone

Status and Prospects of the LHCf and RHICf experiments

Jul 14, 2021, 6:00 PM
1h 30m
03

03

Talk CRI | Cosmic Ray Indirect

Speaker

Hiroaki Menjo (ISEE, Nagoya University)

Description

Precise understanding of hadronic interactions at high energies is a key to improve chemical composition measurements of very high energy cosmic-rays and to solve the muon excess issue observed in high energy cosmic-ray experiments using air-shower technique. The LHCf and RHICf experiments measures the differential production cross sections of very forward neutral particle as photons, neutral pions and neutrons at LHC and RHIC, respectively. These data are critically important to test and tune hadronic interaction models used for air-shower simulations.

In this presentation, we introduce the recent results of both the experiments as well as our future operation plans. LHCf published an updated result of forward neutron measurement at pp, $\sqrt{s}$ = 13 TeV. From the observed neutron energy spectra, we also obtained the average inelasticity, which is one of the key parameters for air shower development, as 0.536 +0.031-0.037. In addition, several analysis are on-going; neutral pion measurement at $pp$, $\sqrt{s}$ = 13 TeV, central- forward correlation analysis with LHCf+ATLAS, photon measurement by RHICf.

LHCf plans to have operations at $pp$ and $p$O during the LHC-Run3 period. At $pp$ collisions, a new silicon readout system will be introduced to improve the read-out speed, and 10 times more statistics of the previous operation in 2015 will be obtained. Thanks to high statistics, rare particles such as $\eta$, $K^0_s$ and $\Lambda$ will be addressed also. We also plan another operation at RHIC in 2024 with a new detector. The detector, a calorimeter composed of tungsten, Si pad and pixel layers, will have a much wider acceptance and higher sensitivity of $K^0_s$ measurement than the current detector.