[PPT] - Constraining Hadron-Hadron interactions with femtoscopy in ALICE PowerPoint Presentation

SLIDE 1

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

Constraining Hadron-Hadron interactions with femtoscopy in ALICE

VA VALENTINA MA MANTOVANI SA SARTI FO FOR THE ALICE COLLABORATION PH PHYSI SIK-DE DEPARTMENT NT - TE TECHNISCHE UN UNIVERSITÄT MÜ MÜNCHEN QN QNP2018– TS TSUK UKUB UBA (TOKYO) - 16 N 16 NOVE VEMBER 2018 2018

SLIDE 2

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

1

G. Baym 13 Nov.
W. Weise 13 Nov.
H. Tamura 13 Nov.
T. Hatsuda 14 Nov.

’Quest for much improved YN and YY database’

SLIDE 3

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

Outline

1. Hadron interactions and Neutron Stars
2. Basics of Femtoscopy in ALICE
3. Results pp 5,7,13 TeV and p-Pb 5.02 TeV
p-p, p-Λ, Λ-Λ, p-Ξ- correlation functions
Λ-Λ exclusion plot and H di-baryon constraints
First observation of the p-Ξ- strong attractive potential
KN-KN: low momenta high precision data to constrain models

close to threshold

2

_

SLIDE 4

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

YN and YY interactions

3

SCATTERING DATA:
Constraint only on pΛ/pΣ interaction (16C1 M.

Kaneta and Y. Nakada)

Data from scattering experiments from 1968

and 1971 in bubble chambers

Production threshold: pLAB ≳100 MeV

LO: H. Polinder, J.H., U. Meiβner, NPA 779 (2006) 244 NLO: J.Haidenbauer., N.Kaiser, et al., NPA 915 (2013) 24

Exp LO NLO

?

SLIDE 5

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

YN and YY interactions: scattering experiments

4

Scattering experiments / Hypernuclei data
SCATTERING DATA:
Constraint only on pΛ/pΣ interaction
Data from scattering experiments from 1968 and

1971 in bubble chambers

Production threshold: pLAB ≳100 MeV
Cannot probe low momentum region

LO: ALWAYS ATTRACTIVE NLO: BECOMES REPULSIVE ⇒ REPULSIVE CORE

LO: H. Polinder, J.H., U. Meiβner, NPA 779 (2006) 244 NLO: J.Haidenbauer., N.Kaiser, et al., NPA 915 (2013) 24

Exp LO NLO

?

SLIDE 6

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

YN and YY interactions: hypernuclei

5

HYPERNUCLEI DATA:
Λ hypernuclei data: B Λ nucleus= 30 MeV
Ξ hypernuclei data show shallow attractive

interaction [Kiso Evt] ⇒ 13C1 Yoshida [IBUKI evt]

ΛΛ hypernuclei exist as well showing weakly

attraction [Nagara Evt] ⇒ 13C1 Yoshida [MINO evt]

Σ hypernuclei: only 4ΣHe observed, ongoing at

JPARC-E13 Coll. 13C1 Nakagawa

SLIDE 7

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

YN and YY interactions: hypernuclei

6

HYPERNUCLEI DATA:
Λ hypernuclei data: B Λ nucleus= 30 MeV
Ξ hypernuclei data show shallow attractive

interaction [Kiso Evt] ⇒ 13C1 Yoshida [IBUKI evt]

ΛΛ hypernuclei exist as well showing weakly

attraction [Nagara Evt] ⇒ 13C1 Yoshida [MINO evt]

Σ hypernuclei: only 4ΣHe observed, ongoing at

JPARC-E13 Coll. 13C1 Nakagawa

SLIDE 8

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

YN and YY interactions: hypernuclei

7

HYPERNUCLEI DATA:
Λ hypernuclei data: B Λ nucleus= 30 MeV
Ξ hypernuclei data show shallow attractive

interaction [Kiso Evt] ⇒ 13C1 Yoshida [IBUKI evt]

ΛΛ hypernuclei exist as well showing weakly

attraction [Nagara Evt] ⇒ 13C1 Yoshida [MINO evt]

Σ hypernuclei: only 4ΣHe observed, ongoing at

JPARC-E13 Coll. 13C1 Nakagawa

T.Nagae et al.PRL80 (1998) 1605-1609

SLIDE 9

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

Hyperon Puzzle in Neutron Stars

9

ChEFT Calculations from: T. Hell, W.W. PRC90 (2014) 045801

Hyperons should appear in dense neutron-rich

matter starting from moderate-large densities

Threshold depends on the Y-N interaction
The appearance of Hyperons softens the EoS
Maximum NS masses get smaller
D. Lonardoni, A. Lovato, S. Gandolfi, F. Pederiva Phys.
Rev. Lett. 114, 092301 (2015)
D. Lonardoni, A. Lovato, S. Gandolfi, F. Pederiva
Phys. Rev. Lett. 114, 092301 (2015)

!"

SLIDE 10

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

BASICS OF FEMTOSCOPY

10

SLIDE 11

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

Basics of Femtoscopy

11

Source function !(# ⃗) # &' &(

Ψ(*, # ⃗)

two particle wave function

§ Look for particle pairs § Measure the relative momentum * distribution in your experimental set up § Search for correlations

SLIDE 12

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

The correlation function

12

The correlation function: ! "∗ = % &', &) % &' % &) , Experimentally obtained as: ! "∗ = + ,

'./("∗)

,234/5("∗) Given by: ! "∗ = 6 7 8, "∗ 9(8, "∗) : ;8 Source Relative Wave Function "∗ → ∞ 1

"∗ = ∣ &'

∗ − &) ∗ ∣

2 and &'

∗ + &) ∗ = 0

SLIDE 13

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

The correlation function

13

The correlation function: ! "∗ = % &', &) % &' % &) , Experimentally obtained as: ! "∗ = + ,

'./("∗)

,234/5("∗) Given by: ! "∗ = 6 7 8, " 9(8, ") : ;8 Assumption of a common source with Gaussian Shape for p-p, p-L, p-X, , L-L and pK Correlation Function Source Relative Wave Function

SLIDE 14

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

The correlation function

14

The correlation function: ! "∗ = % &', &) % &' % &) , Experimentally obtained as: ! "∗ = + ,

'./("∗)

,234/5("∗) Given by: ! "∗ = 6 7 8, " 9(8, ") : ;8 Assumption of a common source with Gaussian Shape for p-p, p-L, p-X, , L-L and pK Correlation Function Source Relative Wave Function Se Sensitivity to

the

in interac actio ion potential ial Strong constraint

SLIDE 15

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

The ALICE data sets

15

! "# "

$

We measure p-p, p-Λ, Λ-Λ, p-Ξ, p-K
Proton identification with TPC and TOF
Reconstruction of hyperons
Λ → '() (BR ~ 64%)
Ξ) → Λ() (BR ~ 100%)
Datasets:
pp 7 TeV:

3.4·108 Events

pp 13 TeV:

10·108 Events

p-Pb 5.02 TeV:

6.0·108 Events

SLIDE 16

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

16

Length scales involved in Femtoscopy

! " = % & ' ⃗ Ψ ", ' ⃗

+

d-' ⃗

.→0

1

§ A-A collisions: 2345ß ~ 4 fm § p-A collisions: 9:;<ß ~ = fm § p-p collisions: 9:;<ß ~ > fm

SLIDE 17

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

17

Correlation function and Interactions

> 1 attraction C(k∗) − → = 1 no interaction < 1 repulsion

Attractive strong interaction No correlations at large momenta Repulsiveness due to strong, Coulomb and Pauli

SLIDE 18

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

Lednicky Model

1 8

Source

Analytic Transport model

Potential

Full Scattering parameters

Correlation function Wave function

Numerically solve the Schrödinger eq.

Eff. range expansion

=> phase shifts

“Exact” solution Approximate solution

Depends on scattering parameters, might locally break down for small sources

SLIDE 19

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

CATS – Correlation Analysis Tool Using the Schrödinger Equation

19 19 19

(D.L.Mihaylov et al. Eur.Phys.J. C78 (2018) no.5,394)

Source

Analytic Transport model

Potential

Full

Scattering parameters

Correlation function Wave function

Numerically solve the Schrödinger eq.

Eff. range expansion

=> phase shifts

“Exact” solution

Approximate solution

SLIDE 20

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

RESULTS

20

SLIDE 21

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

21

Re Results - pp pp collisi sions ns ! = #$ Te TeV

Gaussian source and Argonne n18 potential describes the p-p correlation function
Source size of the pp (7 TeV) system r0=1.14 fm (ALICE Coll. arXiv:1805.12455)
Source size of the pp (13 TeV) system r0=1.19 fm
Source size of the p-Pb (5.02 TeV) system r0=1.38 fm
p-Λ correlation ⇒ strong sensitivity to the source ⇒ detailed investigation on collective effects and

resonance decays ongoing

SLIDE 22

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

22

L-L interaction potentials

Different model predictions for Λ-Λ correlation

function

Χ2 evaluation with all combined datasets and

evaluate the agreement model/data in number of σ deviations

SLIDE 23

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

23

L-L Correlations: Combined Exclusion Plot

Combination of all

available datasets: pp 7 TeV, pp 13 TeV, p-Pb 5.02 TeV

Full scan of scattering

parameters space with the Lednicky model

Test of the agreement

between data and the prediction by the Lednicky model by ns

ATTRACTIVE REPULSIVE BOUND STATE

Au-Au 200 GeV

(STAR data: STAR coll. Phys.Rev.Lett. 114 (2015) no.2,022301)

K. Sasaki and T. Hatsuda (HAL QCD Collaboration), private communication

SLIDE 24

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

24

H-dibaryon binding energies

Set tight constraints on the allowed binding energies
Development of MC bootstrap method to provide a solid

confidence region for scattering parameters and hence BΛΛ

SLIDE 25

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

25

Theoretical p-X- Correlation function

Potential from Hatsuda et al., NPA967 (2017) 856, PoS Lattice2016 (2017) 116) D.L.Mihaylov, V.M.S, O.W.Arnold, L.Fabbietti, B.Hohlweger, A.M.Mathis, Eur.Phys.J. C78 (2018) no.5,394

Comparison Coulomb-only/Coulomb+Strong
Strong potential from preliminary calculations

from HAL-QCD collaboration (13P T.Hatsuda, 16C1 T. Inoue)

! "∗ = 1 8 !'()

*() + !'(, *() + 3

8 !'()

*(, + !'(, *(,

SLIDE 26

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

26

p-X- Correlation Function in p-Pb 5.02 TeV

First observation of strong attractive

interaction in p-X-

modeled with preliminary QCD strong

potential by the HAL QCD collaboration

Potential from Hatsuda et al., NPA967 (2017) 856, PoS Lattice2016 (2017) 116)

! "∗ = 1 8 !'()

*() + !'(, *() + 3

8 !'()

*(, + !'(, *(,

COULOMB-ONLY HYPHOTESIS EXCLUDED AROUND 3σ

SLIDE 27

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

Kaon-Nucleon interaction

27

Bound state?

Y. Ikeda et al Nucl.Phys. A881 (2012) 98-114

plab= 0 KNthreshold Scattering data kaonic atoms

Siddharta er al. Phys.Lett. B704 (2011) G.S. Abrams et al. Phys.Rev. 139 (1965) B454-B457

Note that the effect of pK # ↔ nK #& coupling is not resolved by scat. data

(see 14C1 parallel session)

SLIDE 28

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

Kp and Kp correlations

28

K+p: Repulsive Strong Interaction K-p: Attractive Strong Interaction

__ Jülich Model

(Haidenbauer et al., Phys.Rev. C66 (2002) 055214)

Kyoto Model

(Hyodo et al., Phys.Rev. C95 (2017) no.6,065202)

SLIDE 29

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

Kp and Kp correlations

29

K+p: Repulsive Strong Interaction K-p: Attractive Strong Interaction

__ Jülich Model

(Haidenbauer et al., Phys.Rev. C66 (2002) 055214)

Kyoto Model

(Hyodo et al., Phys.Rev. C95 (2017) no.6,065202)

SLIDE 30

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

Clear effect of the opening of the isospin

breaking channel

Unprecedented constraints for low

energy QCD

Kp correlations

30

Scattering Data

G.S. Abrams et al. Phys.Rev. 139 (1965) B454-B457

Correlation Data

__

!" # ↔ %" #&

SLIDE 31

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

Femtoscopy is an excellent tool to study interactions of particle pairs
Significant sensitivity to the interaction potentials
For hyperons, accesses novel regions not constrained by scattering experiments
Λ-Λ analysis strongly constrains the parameter space for the Λ-Λ interaction ⇒ the

existence of H-dibaryons seems to be disfavored (ALICE coll., Phys. Lett. B 752)

Observation of attractive p-X- interaction for the first time ⇒ set constraints on the

average potential of X hyperons at finite density for NS EoS

In the meson-baryon sector ⇒ First experimental observation of the isospin

breaking opening channel ⇒ constraints close to threshold for low energy QCD models

Extending the study to more hyperons-nucleon pairs (p-Ω, p-Σ0) and in the future to

three-body interactions

In RUN3 ( from 2021 on) we expect factor 100 in statistics!

31

Summary and Outlook:

SLIDE 32

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

You name the pair, we measure it:
Work in progress at the moment: baryon-antibaryon, p-Ω, p-Σ0 Κ-d,….
Universal and Robust Femto Analysis Tool
Fit the correlation function of various systems

simultaneously in combination with CATS

Development of a formalism to study

three particle correlations ⇒ three-body forces including hyperons

32

In the future

SLIDE 33

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62)

Backup Slides

SLIDE 34

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

Current database

34

SLIDE 35

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

The experimental correlation function

35

SLIDE 36

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

Decomposition of the p-p correlation function

36

Purity from MC (Pythia 8)
Feed-down fractions from MC

template fits to the DCAxy distribution

SLIDE 37

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

Decomposition of the p-L correlation function

37

Purity from fits to the

invariant mass distribution

Feed-down fractions from

MC template fits to the cosa distribution

SLIDE 38

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

Decomposition of the L-L correlation function

38

Lambda properties obtained from the L purity and the cosa template fits

SLIDE 39

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

Decomposition of the p-X correlation function

39

Feeding from

W (BR very small)
X0(1530) and X-(1530)
Isospin partners: assume to be

produced in the same amount

X(1530)/X- = 0.32

(https://doi.org/10.1140/epjc/s10052-014- 3191-x)

BR(X0(1530) → X-) = 2/3
BR(X-(1530) → X-) = 1/3

SLIDE 40

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

Some numbers

40

pp@13 TeV P-Pb @ 5.02 TeV

SLIDE 41

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

Epos Source

41 41

(D.L.Mihaylov et al. Eur.Phys.J. C78 (2018) no.5,394)

Source with a non-Gaussian shape Maximum at smaller R and long tail Test with ‘expanded’ EPOS for pp 13 TeV Better Agreement with ‘expanded' EPOS for NLO for p-Λ correlations Gaussian Source EPOS Source

SLIDE 42

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

Collective Effects and Strong Decays

42 42

Elliptic flow Radial flow Strong decays of broad resonances

+ +

p1 p2 R anisotropic pressure gradients within the source Expanding source with constant velocity different effect on different masses are ‘fed’ by resonances with different masses and lifetimes Strong decays of Specific resonances

SLIDE 43

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

Which Resonances?

43 43

Courtesy F. Becattini

SLIDE 44

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

Source Distributions

44 44

SLIDE 45

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

45

L-L Correlations: Predictions with Lednicky

ALI-PREL-144881

Curves represent different points in the L-L exclusion plot
For scattering parameters in the region a0 > 0 the correlation function is not sensitive

SLIDE 46

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

The unique opportunity of small sources

46

Typical short range nuclear potential Gaussian Source Function (RG = 1.5 fm)

SLIDE 47

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

47

Single particle potentials from Lattice

NS environment ⇒ Pure Neutron

Matter

Tested HAL-QCD potential in vacuum

with ALICE ⇒ Brueckner-Hartree- Fock many-body calculations ⇒ UY single-particle potential of hyperons in nucleonic matter

At saturation density in PNM:

UΞ- slightly repulsive

HAL-QCD Collaboration, arXiv:1809.08932 (2018)

SLIDE 48

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

48

Consequences for Neutron Stars

Single-hyperon potential fundamental

ingredient in EoS for NSs

Repulsive interaction⇒Production of

Ξ- pushed to higher densities ⇒ stiffer EoS, higher masses

Weissborn et al., NPA881 (2012) 62-77

SLIDE 49

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

49

p-Ξ- interaction and Neutron Stars

§ If the in-medium N-Ξ potential is not attractive, the EoS becomes stiffer § Ultimately this drives the allowed mass of neutron stars up (even above 2 solar masses) § A complication: in the case of neutron stars

nly the n-Ξ interaction is important, but for us

neutrons are not detectable I=0 I=1 Detectable n-!" X ✓ No p-!# X ✓ Difficult p-!" ✓ ✓ Yes § Experimentally challenging to isolate the I=1 channel

SLIDE 50

Va Valentina Ma Mantovani Sa Sarti (T (TUM P Physics D Department – E6 E62) 16. 16.11. 11.18 18 – QN QNP2018 (Tsuk ukuba uba)

50

Theoretical p-X- Correlation function

Comparison HAL-QCD/χEFT from recent work by Haidenbauer and Meissner (arxiv:1810.04883)