Measurement of exclusive <mml:msup>pi+</mml:msup><mml:msup>pi-</mml:msup> and <mml:msup>rho 0</mml:msup> meson photoproduction at HERA: H1 Collaboration

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F20%3A10421986" target="_blank" >RIV/00216208:11320/20:10421986 - isvavai.cz</a>

Výsledek na webu

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=-uZzVh2rHe" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=-uZzVh2rHe</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1140/epjc/s10052-020-08587-3" target="_blank" >10.1140/epjc/s10052-020-08587-3</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Measurement of exclusive <mml:msup>pi+</mml:msup><mml:msup>pi-</mml:msup> and <mml:msup>rho 0</mml:msup> meson photoproduction at HERA: H1 Collaboration

Popis výsledku v původním jazyce

Exclusive photoproduction of rho 0(770) mesons is studied using the H1 detector at the ep collider HERA. A sample of about 900,000 events is used to measure single- and double-differential cross sections for the reaction gamma p -&gt; pi+pi -Y. Reactions where the proton stays intact (mY=mp) are statistically separated from those where the proton dissociates to a low-mass hadronic system (mp&lt;mY&lt;10&lt;mml:mspace width=&quot;3.33333pt&quot;&gt;&lt;/mml:mspace&gt;GeV). The double-differential cross sections are measured as a function of the invariant mass m pi pi of the decay pions and the squared 4-momentum transfer t at the proton vertex. The measurements are presented in various bins of the photon-proton collision energy W gamma p. The phase space restrictions are 0.5 &lt;= m pi pi &lt;= 2.2&lt;mml:mspace width=&quot;3.33333pt&quot;&gt;&lt;/mml:mspace&gt;GeV, |t|&lt;= 1.5&lt;mml:mspace width=&quot;3.33333pt&quot;&gt;&lt;/mml:mspace&gt;GeV2, and 20 &lt;= W gamma p &lt;= 80&lt;mml:mspace width=&quot;3.33333pt&quot;&gt;&lt;/mml:mspace&gt;GeV. Cross section measurements are presented for both elastic and proton-dissociative scattering. The observed cross section dependencies are described by analytic functions. Parametrising the m pi pi dependence with resonant and non-resonant contributions added at the amplitude level leads to a measurement of the rho 0(770) meson mass and width at m rho =770.8-2.7+2.6&lt;/mml:msubsup&gt;&lt;mml:mspace width=&quot;3.33333pt&quot;&gt;&lt;/mml:mspace&gt;(tot.)&lt;mml:mspace width=&quot;3.33333pt&quot;&gt;&lt;/mml:mspace&gt;MeV and Gamma rho =151.3-3.6+2.7&lt;/mml:msubsup&gt;&lt;mml:mspace width=&quot;3.33333pt&quot;&gt;&lt;/mml:mspace&gt;(tot.)&lt;mml:mspace width=&quot;3.33333pt&quot;&gt;&lt;/mml:mspace&gt;MeV, respectively. The model is used to extract the rho 0(770) contribution to the pi+pi- cross sections and measure it as a function of t and W gamma p. In a Regge asymptotic limit in which one Regge trajectory alpha (t) dominates, the intercept alpha (t=0)=1.0654&lt;mml:mspace width=&quot;4pt&quot;&gt;&lt;/mml:mspace&gt;-0.0067+0.0098&lt;mml:mspace width=&quot;3.33333pt&quot;&gt;&lt;/mml:mspace&gt;(tot.) and the slope alpha &apos; (t=0)=0.233-0.074+0.067&lt;mml:mspace width=&quot;3.33333pt&quot;&gt;&lt;/mml:mspace&gt;(tot.)&lt;mml:mspace width=&quot;3.33333pt&quot;&gt;&lt;/mml:mspace&gt;GeV-2 of the t dependence are extracted for the case &lt;mml:msub&gt;mY=&lt;mml:msub&gt;mp.

Název v anglickém jazyce

Measurement of exclusive <mml:msup>pi+</mml:msup><mml:msup>pi-</mml:msup> and <mml:msup>rho 0</mml:msup> meson photoproduction at HERA: H1 Collaboration

Popis výsledku anglicky

Exclusive photoproduction of rho 0(770) mesons is studied using the H1 detector at the ep collider HERA. A sample of about 900,000 events is used to measure single- and double-differential cross sections for the reaction gamma p -&gt; pi+pi -Y. Reactions where the proton stays intact (mY=mp) are statistically separated from those where the proton dissociates to a low-mass hadronic system (mp&lt;mY&lt;10&lt;mml:mspace width=&quot;3.33333pt&quot;&gt;&lt;/mml:mspace&gt;GeV). The double-differential cross sections are measured as a function of the invariant mass m pi pi of the decay pions and the squared 4-momentum transfer t at the proton vertex. The measurements are presented in various bins of the photon-proton collision energy W gamma p. The phase space restrictions are 0.5 &lt;= m pi pi &lt;= 2.2&lt;mml:mspace width=&quot;3.33333pt&quot;&gt;&lt;/mml:mspace&gt;GeV, |t|&lt;= 1.5&lt;mml:mspace width=&quot;3.33333pt&quot;&gt;&lt;/mml:mspace&gt;GeV2, and 20 &lt;= W gamma p &lt;= 80&lt;mml:mspace width=&quot;3.33333pt&quot;&gt;&lt;/mml:mspace&gt;GeV. Cross section measurements are presented for both elastic and proton-dissociative scattering. The observed cross section dependencies are described by analytic functions. Parametrising the m pi pi dependence with resonant and non-resonant contributions added at the amplitude level leads to a measurement of the rho 0(770) meson mass and width at m rho =770.8-2.7+2.6&lt;/mml:msubsup&gt;&lt;mml:mspace width=&quot;3.33333pt&quot;&gt;&lt;/mml:mspace&gt;(tot.)&lt;mml:mspace width=&quot;3.33333pt&quot;&gt;&lt;/mml:mspace&gt;MeV and Gamma rho =151.3-3.6+2.7&lt;/mml:msubsup&gt;&lt;mml:mspace width=&quot;3.33333pt&quot;&gt;&lt;/mml:mspace&gt;(tot.)&lt;mml:mspace width=&quot;3.33333pt&quot;&gt;&lt;/mml:mspace&gt;MeV, respectively. The model is used to extract the rho 0(770) contribution to the pi+pi- cross sections and measure it as a function of t and W gamma p. In a Regge asymptotic limit in which one Regge trajectory alpha (t) dominates, the intercept alpha (t=0)=1.0654&lt;mml:mspace width=&quot;4pt&quot;&gt;&lt;/mml:mspace&gt;-0.0067+0.0098&lt;mml:mspace width=&quot;3.33333pt&quot;&gt;&lt;/mml:mspace&gt;(tot.) and the slope alpha &apos; (t=0)=0.233-0.074+0.067&lt;mml:mspace width=&quot;3.33333pt&quot;&gt;&lt;/mml:mspace&gt;(tot.)&lt;mml:mspace width=&quot;3.33333pt&quot;&gt;&lt;/mml:mspace&gt;GeV-2 of the t dependence are extracted for the case &lt;mml:msub&gt;mY=&lt;mml:msub&gt;mp.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10303 - Particles and field physics

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2020

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

European Physical Journal C

ISSN

1434-6044

e-ISSN

—

Svazek periodika

80

Číslo periodika v rámci svazku

12

Stát vydavatele periodika

DE - Spolková republika Německo

Počet stran výsledku

54

Strana od-do

1189

Kód UT WoS článku

000603036300007

EID výsledku v databázi Scopus

2-s2.0-85098005273