SNAQ June 2021

Wednesday 9 Jun 2021, 14:45 → 18:30 Europe/Brussels

virtual (online)

Konrad Schmidt (HZDR), Livius Trache (IFIN-HH)

ChETEC-INFRA SNAQs [snacks] Schools on Nuclear Astrophysics Questions

Question in June 2021: What does nuclear physics do for astrophysics?

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Update: Below, all talks are available as PDF for download.

Update: Congratulation to the 2 winners of our SNAQs Scientific Talk Award in recogrecognition and appreciation for giving a scientic talk at the June 2021 edition of SNAQs:

• Heshani Jayatissa (Argonne National Laboratory, United States)
• Hannah Elisabeth Brinkman (Konkoly Observatory, Hungary)

And thanks to all other applicants who submitted an abstract.

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This is the 5th edition of a new, monthly, virtual school format discussing questions related to nuclear astrophysics.

Previous events:

• SNAQ Febrauary 2021
• SNAQ March 2021
• SNAQ April 2021
• SNAQ May 2021

Next event:

• SNAQ October 2021

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We plan to organize a new event of SNAQs always on the 2nd Wednesday in each month with a break in summer (July and August). SNAQs will last about 3.5 hours, including breaks, with lectures and scientific talks around a given question in nuclear astrophysics. Lectures will be held by senior researchers and scientific talks preferably by young researchers, as master and PhD students. Further, SNAQs will put a special focus on the interaction between participants to allow young scientists networking even if traveling to schools, workshops and conferences is not an option.

SNAQs will join the community of schools related to nuclear astrophysics that partner with ChETEC-INFRA:

• Carpathian Summer School of Physics (well established)
• European Summer School on Experimental Nuclear Astrophysics (well established)
• Intercontinental School on Nuclear Astrophysics (new)
• International school on nuclear physics, neutron physics and applications (well established)
• Nuclear Physics in Astrophysics School (new)
• Rußbach School on Nuclear Astrophysics (well established)
• School on observations and spectroscopic tools (new)

The aim of this community is to give all students and young researchers the same, multidisciplinary knowledge about nuclear astrophysics. SNAQs will support this idea and strengthen the community of schools by providing a frequent lecture series to train and educate the next generation of scientist with knowledge across the three types of infrastructures used by nuclear astrophysicists:

• astronuclear laboratories supplying reaction data,
• supercomputer facilities performing stellar structure and nucleosynthesis computations, and
• telescopes and mass spectrometers collecting elemental and isotopic abundance data.

Those infrastructures are networked by ChETEC-INFRA, Chemical Elements as Tracers of the Evolution of the Cosmos - INFRAstructures for Nuclear Astrophysics, a new European starting community of 32 partner institutions.

We are looking forward to meet you at the fifth SNAQ.

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SNAQ June 2021 organizer

SNAQs organizing committee

Livius Trache (Horia Hulubei National Institute for Physics & Nuclear Engineering, Romania)

Rosanna Depalo (University of Padua, Italy) Camilla Juul Hansen (Max Planck Institute for Astronomy Heidelberg, Germany) Marcel Heine (Hubert Curien Pluridisciplinary Institute, France) Ann-Cecilie Larsen (University of Oslo, Norway) Andreas Korn (Uppsala University, Sweden) Arūnas Kučinskas (Vilnius University, Lithuania) Mohamad Moukaddam (University of Strasbourg, France) Sara Palmerini (University of Perugia, Italy) Gianluca Pizzone (Laboratori Nazionali del Sud, Italy) Konrad Schmidt (Helmholtz-Zentrum Dresden-Rossendorf, Germany) Olivier Sorlin (Grand Accélérateur National d'Ions Lourds, France) Livius Trache (Horia Hulubei National Institute for Physics & Nuclear Engineering, Romania) Aurora Tumino (Kore University of Enna, Italy)

Guidelines for participants of SNAQs Please, … … rename yourself in the Zoom sessions to match your registration name and institution – this will serve as your “nametag”. … mute your microphone during talks. … use the public chat only for questions related to the lecture; for discussions, please use the private chat. … write your questions in the chat – due to the high number of participants, a moderator will read a selection of questions but can choose a limited number only. … use breakout rooms to talk and chat to each other in smaller groups. Breakout rooms will be available during coffee breaks and participants can choose rooms freely. … behave professionally and respectfully. … follow ethical standards as professional integrity and honesty. … foster a welcoming and inclusive work environment.

 

14:45 Zoom room available

1 Welcome

Speaker: Konrad Schmidt (Helmholtz-Zentrum Dresden-Rossendorf, Germany)

SNAQs_21_06_1_Konrad_Schmidt.pdf

2 Carpathian Summer School of Physics

Introduction of the school and invitation to the Carpathian Summer School of Physics from August 18 to 27, 2021

Speaker: Livius Trache (Horia Hulubei National Institute for Physics & Nuclear Engineering, Romania)

SNAQs_21_06_2_Livius_Trache.pdf

3 Nuclear physics in astrophysics studies with direct methods using small accelerators

Speaker: György Gyürky (ATOMKI, Hungary)

SNAQs_21_06_3_György_Gyürky.pdf

4 Moderated questions

Speaker: Rosario Gianluca Pizzone (Laboratori Nazionali del Sud, Italy)

5 Nuclear equation of state and physics of compact stars

Speaker: Adriana Raduta (Horia Hulubei National Institute for Physics & Nuclear Engineering, Romania)

SNAQs_21_06_4_Adriana_Raduta.pdf

6 Moderated questions

Speaker: Olivier Sorlin (Grand Accélérateur National d'Ions Lourds, France)

16:35 Coffee break

7 From nuclei to stars – a case in point

Photoneutron reaction cross section measurements on Molybdenum-94 and Zirconium-90 relevant to the p process nucleosynthesis

Speaker: Adriana Banu (James Madison University, United States)

SNAQs_21_06_5_Adriana_Banu.pdf

8 Moderated questions

Speaker: Aurora Tumino (Kore University of Enna, Italy)

9 Breakout session

Breakout rooms are available to (1) very briefly introduce yourself, (2) talk about the lectures, (3) clarify lecture items, and (4) phrase questions for the round table discussion.

Afterwards, questions can be written in the chat of the main Zoom room. Please tag questions related to lecture 1 with L1, questions related to lecture 2 with L2 and lecture 3 with L3. Moderators can only choose a limited number of questions to be discussed at the round table discussion.

This session also povides the opportunity to establish contacts that can be continued using the private chat. Networking is an important tool not only in science.

10 Direct alpha-capture measurement of the 13N(α,p)16O reaction using the MUlti-Sampling Ionization Chamber (MUSIC) relevant for Type Ia supernovae

The 13N(α,p)16O reaction has been recently found to have a significant impact in the estimated high yields of Carbon-13 during the ingestion of hydrogen into the helium shell of massive stars during the shock propagation of a core-collapse supernovae. The rate of this reaction determines the amount of Nitrogen-13 that can β-decay, producing Carbon-13. The reaction rate of the inverse reaction 16O(p,α)13N also plays a role in the creation of Carbon-12 by oxygen burning at high proton abundances via 16O(p,α)13N(γ,p)12C, which in turn affects the abundances of argon and calcium in type Ia supernovae nucleosynthesis. There are only very few experimental data available for the 13N(α,p)16O reaction and the rate of this reaction is not well-constrained. A direct measurement of the 13N(α,p)16O reaction was performed using a 30-MeV secondary beam of Nitrogen-13 from the Argonne In-Flight Radioactive Ion Separator (RAISOR) and the active-target detector MUSIC at Argonne National Laboratory. Preliminary results from this measurement will be discussed.

Speaker: Heshani Jayatissa (Argonne National Laboratory, United States)

SNAQs_21_06_6_Heshani_Jayatissa.pdf

11 Moderated questions

Speaker: Ann-Cecilie Larsen (University of Oslo, Norway)

12 Neutron-capture rates in massive stars: relevance for cosmochemistry

Massive stars eject the products of their nuclear burning into the interstellar medium via stellar winds and supernova explosions. However, these yields are highly dependent on the nuclear reaction rates we implement in our models. We have analysed two science cases for which neutron-capture rates might make a significant impact on the results. The first is that of Chlorine-36 and Calcium-41. Both these isotopes are radio-active and were present in the early Solar System as inferred from meteoritic data. With the current reaction rates implemented in the JINA-reaclib, we determined that to better match the early Solar System abundances with our wind yields, we need either more Chlorine-36 or less Calcium-41, or a combination of the two options. One way to achieve this by testing different values of the main neutron-capture rates responsible of the destruction of the two isotopes in the stellar interior. Our simple tests show that decreasing the Chlorine-36(n,p) rate has little impact on the match with the early Solar System, while increasing the Calcium-41(n,alpha) rate leads to a better match, though there is still a discrepancy in the delay time between these two isotopes of a factor up to 3 derived from these two isotopes, from their wind ejection to the formation of the first solids in the Solar System. The second case where neutron-capture rates have an impact, is that of the production of Chromium-53,54, relative to Chromium-52, and of Titanium-50, relative to Titanium-48, in supernova progenitors. Predicted isotopic ratios of Chromium and Titanium can be used to determine the region of the star from which stardust chromite grains could have originated and the isotopic ratios indicated above are mainly influenced by neutron captures. Therefore, we preformed tests to vary these rates and determine their potential impact on the ratios, which allowed us to determine within nuclear physics uncertainties that the regions of massive stars from which the grains formed could have been the He and the C-shells. Ourwork demonstrates that new experimental determinations of the neutron-capture cross sections discussed above are needed to address cosmochemistry problems.

Speaker: Hannah Elisabeth Brinkman (Konkoly Observatory, Hungary)

SNAQs_21_06_7_Hannah_Elisabeth_Brinkman.pdf

13 Moderated questions

Speaker: Ann-Cecilie Larsen (University of Oslo, Norway)

14 Round table discussion

Questions that were compiled in the chat after during lectures and breakout session will be answered and discussed