Opportunities of OO and pO collisions at the LHC

Europe/Zurich
Zoom (CERN)

Zoom

CERN

Jasmine Therese Brewer (CERN), Aleksas Mazeliauskas (CERN), Wilke van der Schee (CERN)
Description

A summary of the workshop is available at arXiv:2103.01939


The goal of this 5-day workshop is to explore the community perspective on the physics opportunities of oxygen-oxygen and proton-oxygen collisions in the LHC Run 3.

The cosmic-ray community argues for a short pO run during Run 3, because this is the unique time-window for LHCf to take data. In the heavy-ion community, the origin of collectivity in small collision systems remains a central question that begs a timely answer. A more formalised exchange between LHC experiments and theory is clearly an advantage for a successful pO and OO run. Through this workshop, we aim to bring together theorists and experimentalists to discuss both the physics opportunities and challenges specific to OO and pO.

The workshop will provide time for creative discussions on unique opportunities from collisions of light ions. A short summary document of the main conclusions of the workshop will be prepared in advance of the LHCC meeting in March 2021.

Programme:

  • Light-ion beams at the LHC
  • Initial state
  • Soft dynamics of small systems
  • Hard probes in OO and pO
  • Experimental opportunities with OO and pO
  • pO for cosmic-ray physics

Confirmed speakers:

  • Reyes Alemany Fernandez (CERN)
  • Roderik Bruce (CERN)
  • Martino Gagliardi (Universita di Torino)
  • Wojciech Broniowski (IFJ PAN & UJK)
  • Soeren Schlichting (Universitรคt Bielefeld)
  • Wenbin Zhao (Peking University)
  • Chun Shen (Wayne State University)
  • Harri Niemi (University of Jyvรคskylรค)
  • Govert Nijs (MIT)
  • Yuuka Kanakubo (Sophia University)
  • Petja Paakkinen (Universidade de Santiago de Compostela)
  • Alexander Huss (CERN)
  • Liliana Apolinรกrio (LIP)
  • Jacquelyn Noronha-Hostler (University of Illinois at Urbana-Champaign)
  • Man Xie (Central China Normal University)
  • Vytautas Vislavicius (ALICE, Copenhagen University)
  • Igor Altsybeev (ALICE, St Petersburg State University)
  • Anne Marie Sickles (ATLAS, Univ. Illinois at Urbana Champaign)
  • Michael Murray (CMS, University of Kansas)
  • Hans Dembinski (LHCb, MPI Heidelberg)
  • Giacomo Graziani (LHCb/SMOG, INFN Firenze)
  • Hiroaki Menjo (LHCf, Nagoya University)
  • Alessio Tiberio (LHCf, Universita e INFN, Firenze)
  • Tanguy Pierog (KIT, IAP)
  • Dennis Perepelitsa (sPHENIX, CU Boulder)
  • Wei Li (STAR, Rice University)
  • Christian Bierlich (Lund University)

The workshop will take place over five days with a weekend break in the middle: Feb 4-5 and Feb 8-10. Four to five talks each day are scheduled in the late afternoon Geneva time to accommodate different time zones. Each day will be concluded with an extended discussion session to allow an in-depth analysis on the unique opportunities of OO and pO collisions at the LHC.

All talks will be held virtually on Zoom (registration is mandatory to access the links).

Participants
  • Aayush A Verma
  • Abhi Modak
  • Adam Takacs
  • Adrian Aasen
  • Alba Soto-Ontoso
  • Alberto Caliva
  • Aleksander Kusina
  • Aleksas Mazeliauskas
  • Alessia Tricomi
  • Alessia Tricomi
  • Alessio Tiberio
  • Alexander Milov
  • Alexander Philipp Kalweit
  • Alexander Yohei Huss
  • Alexandru Florin Dobrin
  • Alexeii Kurepin
  • Alfred Mishi
  • Alice Ohlson
  • Amanda Lavinia Kjรฆrnsmo
  • Amanda Nicole Flores
  • ameer mukhtar
  • Anatoli Fedynitch
  • Andre Veiga Giannini
  • Andrea Dainese
  • Andrea Dubla
  • Andrea Rossi
  • Andreas Kirchner
  • Andreas Molander
  • Andreas Morsch
  • Anju Bhasin
  • Anna Fehรฉrkuti
  • Anna ร–nnerstad
  • Anne Marie Sickles
  • Anthony Timmins
  • Anton Andronic
  • Arabinda Behera
  • Armando di Matteo
  • Artem Kotliarov
  • Arthur Lopes
  • Arturo Fernandez Tellez
  • Austin Baty
  • Aydan Garibli
  • Baochi Fu
  • Barbara Erazmus
  • Benjamin Audurier
  • Berenice Garcia
  • Bill Zajc
  • Biswarup Paul
  • Bjoern Schenke
  • Boris Tomasik
  • Brian Cole
  • Brian Petersen
  • Bruno Scheihing
  • Camelia Mironov
  • Captain Rituraj Singh
  • Carlos A. Salgado
  • Carlota Andres
  • Charles Gale
  • Chenxi Gu
  • Chi Ding
  • Chiara Oppedisano
  • Chiho Nonaka
  • Chris Flett
  • Christian Bierlich
  • Christoph Schwick
  • Christopher Plumberg
  • Chun Shen
  • Chunjian Zhang
  • Cigdem Issever
  • Clara Elisabeth Leitgeb
  • Cristina Terrevoli
  • Cvetan Valeriev Cheshkov
  • Cyrille Marquet
  • Dananjaya Liyanage
  • Daniel Tapia Takaki
  • Dariusz Miskowiec
  • David d'Enterria
  • David Dobrigkeit Chinellato
  • David Morrison
  • Debjani Banerjee
  • Deepa Thomas
  • Dekrayat Almaalol
  • Dennis Perepelitsa
  • Derek Everett
  • Derek Everett
  • Derek Soeder
  • Derek Teaney
  • Desmond Mzamo Shangase
  • Di Yang
  • Diana Krupova
  • Dmitry Blau
  • Dominik Karol Derendarz
  • Dong Jo Kim
  • Dukhishyam Mallick
  • Dushmanta Sahu
  • Eduardo Grossi
  • Eero Aleksi Kurkela
  • Ejiro Naomi Umaka
  • Ekaterina Eremenko
  • Emil Gorm Nielsen
  • Enrico Scomparin
  • Eva Santos
  • Eva Santos
  • Federica Capellino
  • Federico Antinori
  • Felipe Altran
  • Felix Riehn
  • Fernando Gardim
  • Filip Krizek
  • Filip Moortgat
  • Florian Damas
  • Francesco Prino
  • Frank Geurts
  • Frank Simon
  • Frederique Grassi
  • Fredrick Olness
  • Gabor Veres
  • Georgios Krintiras
  • Giacomo Graziani
  • Gian Michele Innocenti
  • Giovanni Consolati
  • Girija Sankar Pradhan
  • Giulia Manca
  • Giuliano Giacalone
  • Govert Nijs
  • Grazia Luparello
  • Greeshmani Doddi
  • Greg Jackson
  • Guang-You Qin
  • Guilherme Milhano
  • Gyula Bencedi
  • Hadi Mehrabpour
  • Haidar Mas'Ud Alfanda
  • Hannah Elfner
  • Hannu Paukkunen
  • Hans Peter Dembinski
  • Harri Niemi
  • Heungsu Shin
  • Hidetoshi Taya
  • Hiroaki Menjo
  • Hiroaki Menjo
  • Hirotsugu Fujii
  • Hua Pei
  • Huichao Song
  • Hyeonja Jhang
  • Ida Storehaug
  • Igor Altsybeev
  • Igor Pshenichnov
  • Ilya Selyuzhenkov
  • Imanol Corredoira
  • Ismail Soudi
  • Isobel Kolbe
  • Iurii Karpenko
  • Ivan De Mitri
  • Jacopo Ghiglieri
  • Jacquelyn Noronha-Hostler
  • Jakub Cimerman
  • Jakub Vicha
  • Jamal Jalilian-Marian
  • James Lawrence Nagle
  • Jan Fiete Grosse-Oetringhaus
  • Jasmine Therese Brewer
  • Javier Castillo Castellanos
  • Jean-Francois Paquet
  • Jean-Yves Ollitrault
  • Jefferson Sousa
  • Jesse Liu
  • Jesus Guillermo Contreras Nuno
  • Jiangyong Jia
  • Jiayin Sun
  • Jing Wang
  • Jiri Blazek
  • Joao Almeida
  • John Jowett
  • Jonghan Park
  • Jorge Fernandez Soriano
  • Jovan Milosevic
  • Jovan Milosevic
  • Julian Alexander Boelhauve
  • Jurgen Schukraft
  • Jรถrg Hรถrandel
  • Karen Salomรฉ Caballero Mora
  • Kari J. Eskola
  • Katarina Krizkova Gajdosova
  • Katsuaki Kasahara
  • Kevin Ingles
  • Kirill Boguslavski
  • Korinna Zapp
  • Kouki Nakamura
  • Laura Brittany Havener
  • Laura Fabbietti
  • Leonardo Barreto De Oliveira Campos
  • Leticia Cunqueiro Mendez
  • Lev Kheyn
  • Li Yan
  • Liliana Apolinario
  • Liliana Teodorescu
  • Liner Santos
  • Lipei Du
  • Livio Bianchi
  • Lorenzo Bonechi
  • Luca Micheletti
  • Luciano Musa
  • Maciej Rybczynski
  • Man Xie
  • Maowu Nie
  • Marc Andre Jebramcik
  • Marcelo Gameiro Munhoz
  • Marco Femia
  • Marco van Leeuwen
  • Marcos Gonzalez Martinez
  • Maria Vasileiou
  • Maria Vittoria Garzelli
  • Marianna Mazzilli
  • Marie Germain
  • Mario Rodriguez Cahuantzi
  • Mark Strikman
  • Marta Verweij
  • Martin Rybar
  • Martin Spousta
  • Martino Gagliardi
  • Mateusz Ploskon
  • Matt Durham
  • Matt LeBlanc
  • Matthew Heffernan
  • Matthew Luzum
  • Matthew Sievert
  • Maurice Coquet
  • Mauricio Hippert Teixeira
  • Mauricio Martinez Guerrero
  • Maximilian Attems
  • Maximilian Reininghaus
  • Mayank Singh
  • Mebale Tsige
  • Meijian Li
  • Michael Klasen
  • Michael Murray
  • Michael Schmelling
  • Michael Unger
  • Michael Weber
  • Michael Winn
  • Michaela Schaumann
  • Michelangelo Mangano
  • Mihai Petrovici
  • Mikhail Zavertyaev
  • Mikhail Zavertyaev
  • Mikko Kuha
  • Munerah alrashed
  • Nataliya Topilskaya
  • Neelkamal Mallick
  • Nestor Armesto Perez
  • Nicole Bastid
  • Nima Zardoshti
  • Niseem Abdelrahman
  • Oleg Grachov
  • Oleg Grachov
  • Oscar Adriani
  • Oskari Antti Matti Saarimaki
  • Pablo Guerrero Rodrรญguez
  • Panos Christakoglou
  • Pasquale Di Nezza
  • Payal Roy
  • Pedro Mariano
  • Pengqi Yin
  • Percy Alexander Caceres
  • Peter Alan Steinberg
  • Peter Martin Jacobs
  • Petja Paakkinen
  • Pier Francesco Monni
  • Pierre Moreau
  • Pietro Cortese
  • Pinchun Chou
  • Piotr Bozek
  • Pol Gossiaux
  • Pragya Singh
  • Pranjal Sarma
  • Prithwish Tribedy
  • Qingfei Han
  • qinjian lou
  • Radka Sochorovรก
  • Raghav Kunnawalkam Elayavalli
  • Raghunath Sahoo
  • Rahmat Rahmat
  • Raimond Snellings
  • Rajeev S Bhalerao
  • Ralf Ulrich
  • Ralph Engel
  • Ravindra Singh
  • Raymond Ehlers
  • Reyes Alemany Fernandez
  • Riccardo Longo
  • Rihan Haque
  • Risto Paatelainen
  • Robert Szafron
  • Roberta Arnaldi
  • Robin Caron
  • Robin Tรถrnkvist
  • Roderik Bruce
  • Rodrigo Franco
  • Ronald Scaria
  • Rouzbeh Modarresi Yazdi
  • Ruben Conceiรงรฃo
  • Rutuparna Rath
  • Saliha Bashir
  • Sami Rรคsรคnen
  • Samuel Abreu
  • Sanghoon Lim
  • Sarah Porteboeuf
  • Saverio Mariani
  • Sehban Kartal
  • Sergei Nemnyugin
  • Sergei Nemnyugin
  • Sergei Voloshin
  • Seyed Farid Taghavi
  • Shabeeb Alalawi
  • Shahin Hassani
  • Shahin Iqbal
  • Shuai Yang
  • Shuhang Li
  • Shujun Zhao
  • Shuzhe Shi
  • Sijbrand de Jong
  • Silvia Masciocchi
  • Siyu Tang
  • Smita Chakraborty
  • Soeren Schlichting
  • Sohyun Park
  • Somadutta Bhatta
  • Song Zhang
  • Soumya Mohapatra
  • Spencer Robert Klein
  • Sruthy Jyothi Das
  • Stefano Redaelli
  • Suman Deb
  • Sunil Jaiswal
  • Sunil Manohar Dogra
  • Sushanta Tripathy
  • Takashi Sako
  • Takashi Sako
  • Takeshi Osada
  • Takeshi Osada
  • Taku Gunji
  • Takuya Kumaoka
  • Tanguy Pierog
  • Tapan Nayak
  • Tatiana Karavicheva
  • Tetsufumi Hirano
  • Thiago Siqueira Domingues
  • Thiago Siqueira Domingues
  • Thomes Cormier
  • Tolga Altinoluk
  • Tong Liu
  • Tongguang Cheng
  • Tongzhou Guo
  • Topi Lรถytรคinen
  • Torbjรถrn Lundberg
  • Tuomas Lappi
  • Uliana Dmitrieva
  • Ulrich Heinz
  • Urs Wiedemann
  • Valentina Zaccolo
  • Valery Pugatch
  • Varvara Konovalova
  • Victor Gonzalez
  • Victor Manuel Lรณpez Luna
  • Vinh Luong
  • Vishwas Pinto
  • Vitalii Okorokov
  • Vladimir Kovalenko
  • Vladimir Pastushenko
  • Vytautas Vislavicius
  • Wei Li
  • Wenbin Zhao
  • Wilke Van der Schee
  • Wojciech Broniowski
  • Xabier Feal
  • Xiang-Yu Wu
  • Xianglei Zhu
  • Xiaojian Du
  • Xiaoming Zhang
  • Xin-Nian Wang
  • Yang-Ting Chien
  • Yen-Jie Lee
  • Yi Chen
  • Yi Yin
  • Yiheng Luo
  • Yogesh Verma
  • Yoshitaka Itow
  • You Zhou
  • Yu-Gang Ma
  • Yuanyuan Wang
  • Yugang Ma
  • Yuko Sekiguchi
  • Yunxin Ye
  • Yuuka Kanakubo
  • Zahra Abdy
  • Zhengxi Yan
  • Zhenyu Chen
  • Zuzana Moravcova
  • Zvi Citron
    • 14:25 14:30
      Opening 5m
      Speaker: Michelangelo Mangano (CERN)
    • 14:30 15:50
      Light-ion beams at the LHC
      Convener: Dr Marc Andre Jebramcik (DESY (DE))
      • 14:30
        Preparing the CERN Ion Injector Chain for an LHC Oxygen Run 30m

        The preparation of the CERN Ion Injector Chain for an LHC Oxygen Run is not straight forward because the Complex has been designed to deliver Lead beams with a very low radiological impact. With Oxygen beams, initial simulations indicate that we cross the safety borders in terms of personnel and equipment protection. Therefore, special measurements need to be put in place. However, there is nonetheless something positive about Oxygen production, it gives much more beam intensity than Lead, which is really an advantage because LHC can quickly accumulate luminosity. In this talk we summarise the beam intensity expectation across the Ion Injector Complex up to the LHC injection, together with an explanation of the different studies and special measurements that have to be put in place to realise such a run in the CERN Ion Injector Chain.

        Speaker: Reyes Alemany Fernandez (CERN)
      • 15:00
        LHC machine scenario for a short oxygen run 30m

        This talk discusses scenarios for a short oxygen run in the LHC in terms of needed commissioning, machine constraints, beam parameters, and estimated luminosity performance. Both O-O and p-O collisions are discussed.

        Speaker: Dr Roderik Bruce (CERN)
      • 15:30
        Luminosity determination with heavy-ion beams at the LHC 20m
        Speaker: Martino Gagliardi (Universita e INFN Torino (IT))
    • 15:50 16:15
      Discussion
      Conveners: Dr Georgios Krintiras (The University of Kansas (US)), Gian Michele Innocenti (CERN), John Jowett (GSI - Helmholtzzentrum fur Schwerionenforschung GmbH (DE))
      • 15:50
        Discussion on machine development and luminosity 25m
        Speakers: Georgios Krintiras (The University of Kansas (US)), Gian Michele Innocenti (CERN), John Jowett (GSI - Helmholtzzentrum fur Schwerionenforschung GmbH (DE))
    • 16:15 16:30
      Coffee break 15m
    • 16:30 18:05
      Initial state
      Convener: Dekrayat Almaalol (Kent State University)
      • 16:30
        Eccentricities in collisions with 16O and 12C 40m

        I will cover eccentriciteis in collisions with 16O and also 12C, with emphasis on sensitivity to nuclear correlations, in particular, alpha clusterization. Realistic nuclear distribution will be considered and prospects of experimental signatures discussed.

        Speaker: Wojciech Broniowski (IFJ PAN)
      • 17:10
        Initial state and non-equilibrium dynamics in small and large systems 40m
        Speaker: Prof. Soeren Schlichting (Universitรคt Bielefeld)
      • 17:50
        Coffee break 15m
    • 18:05 18:30
      Discussion
      Conveners: Giuliano Giacalone (Universitรฉ Paris-Saclay), Jiangyong Jia (Stony Brook University (US)), Yi Yin (IMP)
      • 18:05
        Discussion on initial state 25m
        Speakers: Giuliano Giacalone (Universitรฉ Paris-Saclay), Jiangyong Jia (Stony Brook University (US)), Yi Yin (IMP)
    • 14:30 15:50
      Soft dynamics of small systems
      Convener: Huichao Song
      • 14:30
        Collectivity and QGP signals in Large and Small systems 40m
        Speaker: Wenbin Zhao (Peking University)
      • 15:10
        Dynamical Modeling of the Collectivity in pO and OO Collisions 40m

        Small collision systems, such as pO and OO, can provide valuable information about the collisions' early-stage dynamics. They also present high sensitivity to initial state fluctuations at multiple length scales. In this talk, we employ the hybrid IP-Glasma + hydrodynamics + hadronic transport approach to simulate the pO and OO collisions' bulk dynamics at the LHC energies. All the model parameters were fixed in the large heavy-ion collisions. We will discuss the challenges of extrapolating the hydrodynamic description to these small systems and identify new aspects of the many-body properties of the hot QCD matter these small systems can probe.

        Speaker: Dr Chun Shen (Wayne State University)
    • 15:50 16:05
      Coffee break 15m
    • 16:05 17:25
      Soft dynamics of small systems
      Convener: Derek Everett (Ohio State University)
      • 16:05
        Multiplicity and flow in O+O collisions from the EKRT model 30m

        We extend the computed EKRT initial conditions from 5 TeV Pb+Pb collisions to O+O collisions at the same collision energy, and compute the subsequent fluid dynamical evolution. We show preliminary predictions for multiplicity and flow observables, and compare the results to the peripheral Pb+Pb collisions at the same collision energy and multiplicity.

        Speaker: Harri Niemi (Johann Wolfgang Goethe-Universitรคt)
      • 16:35
        Bayesian Analysis of Oxygen-Oxygen Collisions 30m

        We use the Trajectum heavy ion code to generate predictions for OO observables, where we use model parameters which are fitted to PbPb data. We subsequently use the OO predictions as mock data for a Bayesian analysis which includes both the PbPb and OO systems, which allows us to estimate the impact of the future addition of OO data on the quality of Bayesian analyses.

        Speaker: Govert Nijs (Massachusetts Institute of Technology)
      • 17:05
        Hadron yield ratios in dynamical core-corona initialization from small to large systems 20m

        The quark-gluon plasma (QGP) formation in small colliding systems is implied from various experimental data at LHC and RHIC. Focusing on one of them, the particle yield ratio, we investigate a possibility of the QGP formation through the dynamical core{corona initialization (DCCI) model. We extend the conventional core{corona picture introducing it into the dynamical initialization framework and demonstrate a dynamical separation of core and corona. In this talk, I give motivation and detailed modeling of the DCCI, and show results of particle yield ratios as a function of multiplicity in p-p, p-Pb and Pb-Pb collisions. I also mention some thoughts on particle yield ratios in p-O and O-O collisions.

        Speakers: Tetsufumi Hirano (Sophia Univ), Yuuka Kanakubo (Sophia Univ.)
    • 17:25 17:40
      Coffee break 15m
    • 17:40 18:30
      Discussion
      Conveners: Bjoern Schenke (Brookhaven National Lab), Jean-Francois Paquet (Duke University), You Zhou (Niels Bohr Institute (DK))
      • 17:40
        Discussion on hydrodynamic modelling 50m
        Speakers: Bjoern Schenke (Brookhaven National Lab), Jean-Francois Paquet (Duke University), You Zhou (Niels Bohr Institute (DK))
    • 14:30 15:40
      Hard probes in pO and OO
      Convener: Michael Klasen
      • 14:30
        Current status of nPDFs and prospects for pO and OO collisions 40m

        The global analyses of nuclear parton distribution functions (nPDFs) are going through a phase of rapid development, driven mainly by new constraints from the CERN LHC protonโ€“lead program, and attracting also new groups to join the field. In this talk, I will review the current status of nPDF global analyses. I will concentrate on the opportunities with lighter-ion runs at the LHC and in particular on the prospects of the proposed protonโ€“oxygen (pO) and oxygenโ€“oxygen (OO) collisions in constraining the mass-number dependence of the nPDFs. As a case study, I will present predictions for dijet production at pO, which has a sizable cross section at the 9.9 TeV collision energy and can thus be expected to give constraints for gluon nuclear modifications even at relatively low luminosities.

        Speaker: Petja Paakkinen (IGFAE - Universidade de Santiago de Compostela)
      • 15:10
        Discovering partonic rescattering in light nucleus collisions 30m
        Speaker: Alexander Yohei Huss (CERN)
    • 15:40 15:55
      Coffee break 15m
    • 15:55 17:25
      Hard probes in pO and OO
      Convener: Dr Isobel Kolbe (Institute for Nuclear Theory)
      • 15:55
        Jet Quenching from light to dense systems 30m

        Results on pA collisions have demonstrated the potential of light systems in achieving the most surprising discoveries. The presence of fluid-like behaviour and their implications motivate further the determination of the necessary conditions that mark the onset of the QGP phase. Intermediate systems, like pO and OO, will be invaluable to a successful unified particle production description from small (pp) to larger (AA) systems. Signatures of medium-induced modifications in the hard sector were, so far, unexistent, or quite limited, putting additional stress on the accurate determination of theoretical and experimental uncertainties. In this talk, we aim to discuss novel theoretical and experimental methodologies, focusing on pO and OO, to characterise the short-wavelength QGP properties with unprecedented precision.

        Speaker: Liliana Apolinario (LIP (PT))
      • 16:25
        The elusive energy loss signal of the Quark Gluon Plasma in OO collisions 40m
        Speaker: Prof. Jacquelyn Noronha-Hostler (University of Illinois Urbana Champaign)
      • 17:05
        $\gamma$-hadron spectra in $p$ + Pb collisions at $\sqrt{s_{\rm NN}}=5.02$ TeV 20m

        Under the assumption that a quark-gluon plasma droplet is produced and its evolution can be described by hydrodynamics in p + A collisions, $\gamma$-triggered hadron spectra \cite{Wang:1996yh, Zhang:2009rn} are studied within a next-to-leading-order perturbative QCD parton model with the medium-modified parton fragmentation functions. The initial conditions and space-time evolution of the small QGP droplet are provided by the superSONIC hydrodynamic model \cite{Weller:2017tsr} simulations and parton energy loss in such a medium is described by the high-twist (HT) approach \cite{Wang:2009qb}. The range of scaled jet transport coefficient $\hat{q}_0/T_0^3$ in this HT approach is extracted from single hadron suppression in A + A collisions with similar initial medium temperature as in p + A collisions. Numerical results for this scenario show that $\gamma$-hadron spectra at $p_{\rm T}^\gamma=12-40$ GeV/$c$ are suppressed by 5 $-$ 15\% in the most central 0 - 10\% p + Pb collisions at $\sqrt{s_{\rm NN}}=5.02$ TeV. The suppression becomes weaker at higher transverse momentum of the $\gamma$ trigger. As a comparison, $\gamma$-hadron suppression in Pb + Pb collisions at $\sqrt{s_{\rm NN}}=2.76$ and 5.02 TeV is also predicted.

        Speaker: Man Xie (Central China Normal University)
    • 17:25 17:40
      Coffee break 15m
    • 17:40 18:30
      Discussion
      Conveners: Carlota Andres (LIP, Lisbon), Marco Van Leeuwen (Nikhef National institute for subatomic physics (NL)), Dr Xin-Nian Wang (Lawrence Berkeley National Lab. (US))
      • 17:40
        Discussion session on hard probes 50m
        Speakers: Carlota Andres (LIP, Lisbon), Marco Van Leeuwen (Nikhef National institute for subatomic physics (NL)), Xin-Nian Wang (Lawrence Berkeley National Lab. (US))
    • 14:30 15:50
      Experimental opportunities with OO and pO
      Convener: Deepa Thomas (University of Texas at Austin (US))
    • 15:50 16:05
      Coffee break 15m
    • 16:05 17:25
      Experimental opportunities with OO and pO
      Convener: Austin Alan Baty (Rice University (US))
      • 16:05
        Physics opportunities with oxygen collisions in CMS 40m

        Oxygen on oxygen, proton oxygen and photon oxygen collisions at the LHC offer rich physics opportunities both in themselves and as compliments to the current lead based heavy ion program. The extensive rapidity coverage, excellent event reconstruction, and flexible trigger system of CMS make it an ideal detector for exploiting such opportunities. This talk will review potential oxygen measurements with CMS and describe some of the challenges in making such measurements a reality.

        Speaker: Michael Murray (The University of Kansas (US))
      • 16:45
        Oxygen beams and LHCb: prospects of pO and OO collisions for nuclear and astroparticle physics 20m
        Speaker: Dr Hans Peter Dembinski (TU Dortmund)
      • 17:05
        Oxygen beams and LHCb: prospects of collisions with fixed-targets 20m

        The LHCb experiment has the unique possibility, among the LHC
        experiments, to be operated in fixed target mode using its internal gas
        target. After reviewing the results achieved so far in the fixed target
        configuration, we will discuss prospects for the incoming run, where,
        thanks to the upgraded target system, a significant improvement in
        luminosity and a wider choice of the target gas are expected.
        The possibility of running with oxygen beams offers novel possibilities
        for nuclear and astroparticle physics. In particular, collisions of O beams
        on a hydrogen target can provide measurements of identified charged
        particle production up to very forward rapidity in the O nucleus rest frame.

        Speaker: Giacomo Graziani (INFN, Sezione di Firenze (IT))
    • 17:25 17:40
      Coffee break 15m
    • 17:40 18:30
      Discussion
      Conveners: Alice Ohlson (Lund University (SE)), Dr Guilherme Milhano (LIP-Lisbon & CERN TH), Yen-Jie Lee (Massachusetts Inst. of Technology (US))
      • 17:40
        Discussion on experimental opportunities 50m
        Speakers: Alice Ohlson (Lund University (SE)), Guilherme Milhano (LIP-Lisbon & CERN TH), Yen-Jie Lee (Massachusetts Inst. of Technology (US))
    • 14:30 15:50
      pO for cosmic-ray physics
      Convener: Lorenzo Bonechi (Istituto Nazionale di Fisica Nucleare (INFN))
      • 14:30
        LHCf achievements at pp and pPb 15m

        The aim of the LHC forward (LHCf) experiment is to provide critical data to test and tune hadronic interaction models used for very high energy cosmic-ay interactions. LHCf measures neutral particles, photons, neutrinos and pi0s, at very forward region of LHC collisions, and these energetic particles significantly contribute air shower development induced by cosmic-rays. LHCf had several operations with pp and pPb collisions during Run1 and Run2 and published several results. In this talk, we will discuss about these achievement as an introduction of the following talk focusing on pO.

        Speakers: Hiroaki Menjo (Nagoya University (JP)), Hiroaki Menjo (Nagoya University (JP))
      • 14:45
        LHCf motivations and prospects of p-O collisions 25m

        A proton-oxygen run at the LHC would be a unique opportunity to reproduce the collision of a cosmic ray with a light nucleus of the atmosphere. The LHCf experiment will have the possibility to perform direct measurements of the very-forward neutral particle production and the nuclear modification factor without the need of an interpolation of the results in proton-proton and proton-lead collisions. Another advantage of p-O collision is the much smaller contribution of Ultra Peripheral Collisions to the particle production with respect to the p-Pb case, which will lead to more precise measurements for the tuning of the phenomenological hadronic interaction models. LHCf will be able to operate both on the p-remnant and O-remnant side with a dedicated low-luminosity run. A common operation with the ATLAS ZDC is also under discussion.

        Speaker: Alessio Tiberio (Universita e INFN, Firenze (IT))
      • 15:10
        Hadronic interactions and air showers : the need of Oxygen beam with LHCf 40m

        In detailed air shower simulations, the uncertainty in the prediction of shower observable for different primary particles and energies is currently dominated by differences between hadronic interaction models. With the general results of the first run of the LHC, the difference between post-LHC model predictions has been reduced at the same level than experimental uncertainties of cosmic ray experiments for Xmax measurements, but a deficit in muon production in simulation remains. At the same time new type of air shower observable, like the muon production depth, has been measured adding new constraints on hadronic models. Currently no model is able to reproduce consistently all mass composition measurement possible within the Pierre Auger Observatory for instance. In parallel, only few new measurements at LHC are providing new tests of the models which could help understanding the remaining differences between observed and simulated air showers. LHCf is the only LHC experiment testing the model used for such simulations in the relevant phase space and in combination with central trigger. The measurements in Run 1 and 2, already showed deficiency in the models. Results of LHCf with Oxygen beam which will include the nuclear effects missing in p-p collisions, as originally planed in Run 3, would be crucial to get enough information to solve the problems observed in a proper way and early enough that it can still be applied in the analysis of the current largest cosmic ray experiments.

        Speaker: Dr Tanguy Pierog (KIT)
    • 15:50 16:15
      Discussion
      Conveners: Alessia Tricomi (Universita e INFN, Catania (IT)), David d'Enterria (CERN)
      • 15:50
        Discussion on forward physics and cosmic rays 25m
        Speakers: Alessia Tricomi (Universita e INFN, Catania (IT)), David d'Enterria (CERN)
    • 16:15 16:30
      Coffee break 15m
    • 16:30 17:10
      Experimental opportunities with OO and pO
      Convener: David Dobrigkeit Chinellato (University of Campinas UNICAMP (BR))
    • 17:10 17:50
      Soft dynamics of small systems
      Convener: David Dobrigkeit Chinellato (University of Campinas UNICAMP (BR))
      • 17:10
        A Pythia/Angantyr perspective on OO and pO collisions 40m
        Speaker: Christian Bierlich (Lund University (SE))
    • 17:50 18:15
      Discussion
      Conveners: Iurii Karpenko (SUBATECH Nantes), Prithwish Tribedy (Brookhaven National Lab), Raghav Kunnawalkam Elayavalli (Yale University)
      • 17:50
        Discussion on on Monte Carlo modelling and experimental opportunities at RHIC 25m
        Speakers: Iurii Karpenko (SUBATECH Nantes), Prithwish Tribedy (Brookhaven National Lab), Raghav Kunnawalkam Elayavalli (Yale University)
    • 18:15 18:30
      Coffee break 15m
    • 18:30 19:00
      Discussion: Workshop summary
      Conveners: Jasmine Therese Brewer (CERN), Dr Aleksas Mazeliauskas (CERN), Dr Wilke Van Der Schee (CERN)
      • 18:30
        Workshop summary 30m
        Speakers: Dr Aleksas Mazeliauskas (CERN), Jasmine Therese Brewer (CERN), Dr Wilke Van Der Schee (CERN)
    • 19:00 19:05
      Closing 5m