دانشکده فیزیک
سمینار کیهانشناسی و اخترفیزیک
امواج گرانشی حاصل از تورم غیر جاذب و داده های نانوگرو (بخش دوم)
Induced gravitational waves from non-attractor inflation and NANOGrav data
دکتر امین نصیری
دانشکده فیزیک، دانشگاه صنعتی خواجه نصیر
چکیده: در این سخنرانی در مورد امواج گرانشی حاصل از تورم غیر جاذب صحبت خواهم کرد. به این منظور ابتدا مرور مختصری بر تورم و تورم غیر جاذب خواهم داشت. در ادامه در مورد آرایه زمان سنجی تپ اخترها به عنوان آشکارسازی برای امواج گرانشی صحبت خواهم کرد. در پایان در مورد پیش بینی تورم غیر جاذب در مورد امواج گرانشی صحبت کرده و نتایج را با داده های نانوگرو مقایسه خواهم کرد.
Abstract: In this talk I will talk about the induced gravitational waves from non-attractor inflation. To this end firstly, I will give a brief review about inflation and the non- attractor inflation. Then I will talk about the pulsar timing arrays as a detector of gravitational waves. Finally I will proceed with prediction of non-attractor inflation for the induced gravitational waves and compare the results with the data of NANOGrav.
زمان: ۴ تیر ۱۴۰۳ – ساعت ۱۶ الی ۱۷
مکان: سالن اجتماعات دکتر ابوالحسنی
حضور مجازی: meet.google.com/phx-pdzw-cwg
سمینار کیهانشناسی و اخترفیزیک
امواج گرانشی حاصل از تورم غیر جاذب و داده های نانوگرو (بخش دوم)
Induced gravitational waves from non-attractor inflation and NANOGrav data
دکتر امین نصیری
دانشکده فیزیک، دانشگاه صنعتی خواجه نصیر
چکیده: در این سخنرانی در مورد امواج گرانشی حاصل از تورم غیر جاذب صحبت خواهم کرد. به این منظور ابتدا مرور مختصری بر تورم و تورم غیر جاذب خواهم داشت. در ادامه در مورد آرایه زمان سنجی تپ اخترها به عنوان آشکارسازی برای امواج گرانشی صحبت خواهم کرد. در پایان در مورد پیش بینی تورم غیر جاذب در مورد امواج گرانشی صحبت کرده و نتایج را با داده های نانوگرو مقایسه خواهم کرد.
Abstract: In this talk I will talk about the induced gravitational waves from non-attractor inflation. To this end firstly, I will give a brief review about inflation and the non- attractor inflation. Then I will talk about the pulsar timing arrays as a detector of gravitational waves. Finally I will proceed with prediction of non-attractor inflation for the induced gravitational waves and compare the results with the data of NANOGrav.
زمان: ۴ تیر ۱۴۰۳ – ساعت ۱۶ الی ۱۷
مکان: سالن اجتماعات دکتر ابوالحسنی
حضور مجازی: meet.google.com/phx-pdzw-cwg
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علاقهمندید کدام محتویات زیر را بیشتر در کانال ببینید؟
anonymous poll
موقعیتهای دکترا و پسادکترا در کشورهای مختلف – 17
👍👍👍👍👍👍👍 40%
اطلاع رسانی سمینارها و وبینارهای علمی – 10
👍👍👍👍 24%
اخبار دنیای اخترفیزیک و کیهانشناسی – 8
👍👍👍 19%
آخرین مقالات آرکایوی منتشر شده در حوزه اخترفیزیک و کیهانشناسی – 5
👍👍 12%
اخبار دنیای علم به صورت کلی – 2
👍 5%
👥 42 people voted so far.
anonymous poll
موقعیتهای دکترا و پسادکترا در کشورهای مختلف – 17
👍👍👍👍👍👍👍 40%
اطلاع رسانی سمینارها و وبینارهای علمی – 10
👍👍👍👍 24%
اخبار دنیای اخترفیزیک و کیهانشناسی – 8
👍👍👍 19%
آخرین مقالات آرکایوی منتشر شده در حوزه اخترفیزیک و کیهانشناسی – 5
👍👍 12%
اخبار دنیای علم به صورت کلی – 2
👍 5%
👥 42 people voted so far.
🇦🇺PhD Scholarships in Astrophysics🇦🇺
Institution
University of Melbourne
Department
School of Physics
Number of Positions Available
10
Work Arrangement
In-Person
In-Person Location(s)
Parkville VIC
Australia
Job Denoscription
We invite applications from exceptionally talented students planning a PhD in astrophysics or cosmology for PhD scholarships at the University of Melbourne.
The University of Melbourne is engaged in cutting edge research in observational and theoretical astrophysics, cultural and Indigenous astronomy, high energy astrophysics and transients, state of the art simulations of the early Universe, LIGO gravitational wave analysis, high-redshift galaxies, the cosmic microwave background, and 21 cm observations. The group leads SpIRIT - the first mission of the Australian Space Agency which launched in 2023 and will detect and study high energy transients and gravitational wave counterparts. The group also hosts nodes of two research centres, OzGRAV and ASTRO-3D.
The scholarships come with a tax-free stipend of AUD$37,000/yr (in 2024) for 3.5 years.
Applicants should submit an Expression of Interest through the link, including a statement of research interests, CV, trannoscripts if possible, and two reference letters by July 26 (this deadline is for international students). Successful candidates will be supported through the formal U. Melbourne application process.
Established in 1853, the University of Melbourne helps graduates become well-rounded, thoughtful and skilled professionals who make a positive impact across the globe. It's consistently ranked among the leading universities in the world, with international rankings placing it as #1 in Australia and #31 in the world (THE World Rankings 2021). Our research helps solve challenges the world is facing today and into the future. We're tightly connected with our communities, at home and around the globe; a connection that enriches our learning, teaching and research. The University of Melbourne offers an unsurpassed learning experience on an urban campus located on the edge of downtown Melbourne. Melbourne, a bustling metropolis of around 5 million people, frequently stars on lists of the most liveable cities in the world.
Compensation and Benefits
Compensation Type
Salary
Currency
323
Stipend
$37,000.00AUD
Application Details
Link to Online Application
https://forms.gle/NDsySwincyCJQyjj7
Publication Start Date
2024 Jun 27
Application Deadline
2024 Jul 26
Inquiries
Name
Astrophysics Selection Panel
Email
astrophysics@lists.unimelb.edu.au
Institution
University of Melbourne
Department
School of Physics
Number of Positions Available
10
Work Arrangement
In-Person
In-Person Location(s)
Parkville VIC
Australia
Job Denoscription
We invite applications from exceptionally talented students planning a PhD in astrophysics or cosmology for PhD scholarships at the University of Melbourne.
The University of Melbourne is engaged in cutting edge research in observational and theoretical astrophysics, cultural and Indigenous astronomy, high energy astrophysics and transients, state of the art simulations of the early Universe, LIGO gravitational wave analysis, high-redshift galaxies, the cosmic microwave background, and 21 cm observations. The group leads SpIRIT - the first mission of the Australian Space Agency which launched in 2023 and will detect and study high energy transients and gravitational wave counterparts. The group also hosts nodes of two research centres, OzGRAV and ASTRO-3D.
The scholarships come with a tax-free stipend of AUD$37,000/yr (in 2024) for 3.5 years.
Applicants should submit an Expression of Interest through the link, including a statement of research interests, CV, trannoscripts if possible, and two reference letters by July 26 (this deadline is for international students). Successful candidates will be supported through the formal U. Melbourne application process.
Established in 1853, the University of Melbourne helps graduates become well-rounded, thoughtful and skilled professionals who make a positive impact across the globe. It's consistently ranked among the leading universities in the world, with international rankings placing it as #1 in Australia and #31 in the world (THE World Rankings 2021). Our research helps solve challenges the world is facing today and into the future. We're tightly connected with our communities, at home and around the globe; a connection that enriches our learning, teaching and research. The University of Melbourne offers an unsurpassed learning experience on an urban campus located on the edge of downtown Melbourne. Melbourne, a bustling metropolis of around 5 million people, frequently stars on lists of the most liveable cities in the world.
Compensation and Benefits
Compensation Type
Salary
Currency
323
Stipend
$37,000.00AUD
Application Details
Link to Online Application
https://forms.gle/NDsySwincyCJQyjj7
Publication Start Date
2024 Jun 27
Application Deadline
2024 Jul 26
Inquiries
Name
Astrophysics Selection Panel
astrophysics@lists.unimelb.edu.au
🇦🇹 PhD and Postdoc Positions in Lorentzian Geometry/General Relativity/Metric Geometry, Vienna, Austria 🇦🇹
Contact: ef-applications.mathematics[AT]univie.ac.at
Location: Vienna, Austria
We are seeking to fill up to five PhD and four Postdoc positions within the research project
A new Geometry for Einstein’s Theory of Relativity and beyond
The project is situated at the intersection of Lorentzian Geometry, General Relativity, Metric Geometry and Optimal Transport, and has received major funding by the Austrian Science Fund (FWF) in the framework of its “Emerging Fields” program.
We are looking for exceptional candidates with a strong background in at least one, preferably several, of the following fields: Riemannian/Lorentzian geometry, functional analysis and measure theory, optimal transport, metric geometry, calculus of variations, geometric analysis, mathematical General Relativity.
https://ef-geometry.univie.ac.at/call-for-praedoc-and-postdoc-positions/
Contact: ef-applications.mathematics[AT]univie.ac.at
Location: Vienna, Austria
We are seeking to fill up to five PhD and four Postdoc positions within the research project
A new Geometry for Einstein’s Theory of Relativity and beyond
The project is situated at the intersection of Lorentzian Geometry, General Relativity, Metric Geometry and Optimal Transport, and has received major funding by the Austrian Science Fund (FWF) in the framework of its “Emerging Fields” program.
We are looking for exceptional candidates with a strong background in at least one, preferably several, of the following fields: Riemannian/Lorentzian geometry, functional analysis and measure theory, optimal transport, metric geometry, calculus of variations, geometric analysis, mathematical General Relativity.
https://ef-geometry.univie.ac.at/call-for-praedoc-and-postdoc-positions/
ef-geometry.univie.ac.at
Call for praedoc (PhD students) and postdoc positions – A new Geometry for Einstein’s Theory of Relativity & Beyond
Emerging Fields project - A new Geometry for Einstein’s Theory of Relativity & Beyond. This project is funded by the FWF and based at the Faculty of Mathematics of the University of Vienna
Journal Club: Experiments & Phenomenology / Hybrid format
Date:
Monday, Jul 1, 2024 / دوشنبه، 11 تیر 1403
Time:
11:00 AM - 12:00 PM (Tehran time)
Speaker:
Dr. Saeedeh Afhami
Affiliation:
Iranian Light Source Facility & School of Particles and Accelerators, IPM
Title:
Non-Evapourable Getters Coating, a novel route to achieve ultra high vacuum
Title in Persian:
لایه نشانی جاذب های غیر تبخیری، مسیری جدید برای دستیابی به خلاء بسیار بالا
Abstract:
The search for an effective solution to the problem of pumping conductance-limited vacuum systems, as those for particle accelerators, lead, at the end of 1995, to the start of the development of Non-Evaporable Getters (NEG) thin film coatings at CERN. Coating the whole inner surface of a vacuum chamber, after dissolving the NEG oxide layer by heating (activation), transforms it from a source of
gas into a pump providing very high pumping speed per unit length. In this talk, we will present the NEG physics and also describe how discharge voltage, magnetic field strength, and pressure effect on the deposition rate.
Based on: https://arxiv.org/pdf/2006.01537
Meeting Place: Seminar Room, School of Particles and Accelerators, IPM
Link to Join Virtually: https://meet.google.com/bda-vsem-tuv
Date:
Monday, Jul 1, 2024 / دوشنبه، 11 تیر 1403
Time:
11:00 AM - 12:00 PM (Tehran time)
Speaker:
Dr. Saeedeh Afhami
Affiliation:
Iranian Light Source Facility & School of Particles and Accelerators, IPM
Title:
Non-Evapourable Getters Coating, a novel route to achieve ultra high vacuum
Title in Persian:
لایه نشانی جاذب های غیر تبخیری، مسیری جدید برای دستیابی به خلاء بسیار بالا
Abstract:
The search for an effective solution to the problem of pumping conductance-limited vacuum systems, as those for particle accelerators, lead, at the end of 1995, to the start of the development of Non-Evaporable Getters (NEG) thin film coatings at CERN. Coating the whole inner surface of a vacuum chamber, after dissolving the NEG oxide layer by heating (activation), transforms it from a source of
gas into a pump providing very high pumping speed per unit length. In this talk, we will present the NEG physics and also describe how discharge voltage, magnetic field strength, and pressure effect on the deposition rate.
Based on: https://arxiv.org/pdf/2006.01537
Meeting Place: Seminar Room, School of Particles and Accelerators, IPM
Link to Join Virtually: https://meet.google.com/bda-vsem-tuv
Seminar / Virtual format
Date:
Wednesday, Jul 3, 2024 / چهارشنبه، 13 تیر 1403
Time:
11:00 AM - 12:00 PM (Tehran time)
Speaker:
Mr. Mohammad Aghaie
Affiliation:
University of Pisa and INFN sezione di Pisa
Title:
Minimal Dark Matter and its Indirect Detection
Title in Persian:
مدل ماده تاریک مینیمال و شناسایی غیرمستقیم آن
Abstract:
In this study, we investigate the sensitivity of the Cherenkov Telescope Array (CTA) and Fermi Large Area Telescope (Fermi-LAT) to dark matter (DM) annihilation in γ-ray lines. We focus on observations of the Galactic Center (GC), dwarf Spheroidal galaxies (dSphs), and galaxy clusters (GCls). Specifically, we compare the reach of the GC with that of dSphs, considering the poorly known putative core radius of the DM distribution. Surprisingly, we find that the currently best dSph candidates present a more promising target than the GC, especially for core radii ranging from one to a few kiloparsecs.
In addition to CTA prospects, we extend our analysis to incorporate Fermi-LAT data. Recent advancements in computations have highlighted the impact of Sommerfeld enhancement and bound-state formation on the annihilation cross section of Minimal Dark Matter (MDM) multiplets. Exploring this new paradigm, we examine Fermi-LAT data to assess its capability to detect or rule out a potential line arising from bound-state formation processes. Our findings reveal that the Fermi-LAT data effectively rules out the MDM 5plet at a significance level of 2σ, demonstrating the importance of considering enhanced cross sections and new annihilation signatures in the quest to unravel the mysteries of dark matter.
Indico Link: https://indico.hep.ipm.ir/e/m.aghaie
Meeting Place: Seminar Room, School of Particles and Accelerators, IPM
Link to Join Virtually: https://meet.google.com/bda-vsem-tuv
Date:
Wednesday, Jul 3, 2024 / چهارشنبه، 13 تیر 1403
Time:
11:00 AM - 12:00 PM (Tehran time)
Speaker:
Mr. Mohammad Aghaie
Affiliation:
University of Pisa and INFN sezione di Pisa
Title:
Minimal Dark Matter and its Indirect Detection
Title in Persian:
مدل ماده تاریک مینیمال و شناسایی غیرمستقیم آن
Abstract:
In this study, we investigate the sensitivity of the Cherenkov Telescope Array (CTA) and Fermi Large Area Telescope (Fermi-LAT) to dark matter (DM) annihilation in γ-ray lines. We focus on observations of the Galactic Center (GC), dwarf Spheroidal galaxies (dSphs), and galaxy clusters (GCls). Specifically, we compare the reach of the GC with that of dSphs, considering the poorly known putative core radius of the DM distribution. Surprisingly, we find that the currently best dSph candidates present a more promising target than the GC, especially for core radii ranging from one to a few kiloparsecs.
In addition to CTA prospects, we extend our analysis to incorporate Fermi-LAT data. Recent advancements in computations have highlighted the impact of Sommerfeld enhancement and bound-state formation on the annihilation cross section of Minimal Dark Matter (MDM) multiplets. Exploring this new paradigm, we examine Fermi-LAT data to assess its capability to detect or rule out a potential line arising from bound-state formation processes. Our findings reveal that the Fermi-LAT data effectively rules out the MDM 5plet at a significance level of 2σ, demonstrating the importance of considering enhanced cross sections and new annihilation signatures in the quest to unravel the mysteries of dark matter.
Indico Link: https://indico.hep.ipm.ir/e/m.aghaie
Meeting Place: Seminar Room, School of Particles and Accelerators, IPM
Link to Join Virtually: https://meet.google.com/bda-vsem-tuv
Indico
Wednesday weekly meeting
Weekly general meeting of the school of particles and accelerators (virtual) Link to join: https://meet.google.com/bda-vsem-tuv
Forwarded from Theoretical_Physics (Ghadir Jafari)
اثر امپمبا به این مشاهده گفته میشود که آب گرم زود تر از آب سرد یخ میزند. این پدیده به خاطر اراستو امپمبا تازانیایی نامگذاری شده است که اولین بار به عنوان یک دانشآموز در مدرسه در سال ۱۹۶۳ این مشاهده را انجام داده است.
هر چند روی وجود این پدیده و شرایط آن هنوز اختلاف نظرهایی وجود دارد اما توضیحات مختلفی هم برای وجود دارد.
در هفته گذشته سه مقاله در مجله prl چاپ شده که ورژن کوانتومی این پدیده را بررسی کرده اند و چالش های جدیدی را برای ترمودینامیک کوانتومی به وجود آورده است.
Observing the Quantum Mpemba Effect in Quantum Simulations
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.133.010402
Microscopic Origin of the Quantum Mpemba Effect in Integrable Systems
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.133.010401
Inverse Mpemba Effect Demonstrated on a Single Trapped Ion Qubit
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.133.010403
خلاصه را در خبر زیر می توانید ببینید:
Exploring Quantum Mpemba Effects
https://physics.aps.org/articles/v17/105
هر چند روی وجود این پدیده و شرایط آن هنوز اختلاف نظرهایی وجود دارد اما توضیحات مختلفی هم برای وجود دارد.
در هفته گذشته سه مقاله در مجله prl چاپ شده که ورژن کوانتومی این پدیده را بررسی کرده اند و چالش های جدیدی را برای ترمودینامیک کوانتومی به وجود آورده است.
Observing the Quantum Mpemba Effect in Quantum Simulations
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.133.010402
Microscopic Origin of the Quantum Mpemba Effect in Integrable Systems
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.133.010401
Inverse Mpemba Effect Demonstrated on a Single Trapped Ion Qubit
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.133.010403
خلاصه را در خبر زیر می توانید ببینید:
Exploring Quantum Mpemba Effects
https://physics.aps.org/articles/v17/105
Wednesday Weekly Seminar – Hybrid Format
Date:
Wednesday, July 10, 2024 / چهارشنبه، 20 تیر 1403
Time:
11:00 AM - 12:00 PM (Tehran time)
Speaker:
Dr. Hamed Abdolmaleki
Affiliation:
Malayer University & IPM
Title:
Exploring SMEFT Couplings Using the Forward-Backward Asymmetry in Neutral Current Drell-Yan Production at the LHC
Title in Persian:
بررسی کوپلینگهای نظریه میدانهای موثر مدل استاندارد در شتابدهنده بزرگ هادرونی
Abstract:
Neutral current Drell-Yan (DY) lepton-pair production is considered in the framework of the Standard Model Effective Field Theory (SMEFT). Using the open-source fit platform xFitter, we investigate the impact of high-statistics measurements of the neutral current DY (NCDY) forward-backward asymmetry AFB near the weak boson mass scale in the present and forthcoming stages of the Large Hadron Collider (LHC). Besides recovering earlier results on the AFB sensitivity to parton distribution functions, we analyze the precision determination of Z-boson couplings to left-handed and right-handed u-quarks and d-quarks, and explore Beyond-Standard-Model contributions using the SMEFT framework. We comment on the role of the AFB asymmetry for the electroweak SMEFT fit and precision Z-boson physics at the LHC and high-luminosity HL-LHC.
Indico Link: https://indico.hep.ipm.ir/e/h.abdolmaleki2
Meeting Place: Seminar Room, School of Particles and Accelerators, IPM
Link to Join Virtually: https://meet.google.com/bda-vsem-tuv
Date:
Wednesday, July 10, 2024 / چهارشنبه، 20 تیر 1403
Time:
11:00 AM - 12:00 PM (Tehran time)
Speaker:
Dr. Hamed Abdolmaleki
Affiliation:
Malayer University & IPM
Title:
Exploring SMEFT Couplings Using the Forward-Backward Asymmetry in Neutral Current Drell-Yan Production at the LHC
Title in Persian:
بررسی کوپلینگهای نظریه میدانهای موثر مدل استاندارد در شتابدهنده بزرگ هادرونی
Abstract:
Neutral current Drell-Yan (DY) lepton-pair production is considered in the framework of the Standard Model Effective Field Theory (SMEFT). Using the open-source fit platform xFitter, we investigate the impact of high-statistics measurements of the neutral current DY (NCDY) forward-backward asymmetry AFB near the weak boson mass scale in the present and forthcoming stages of the Large Hadron Collider (LHC). Besides recovering earlier results on the AFB sensitivity to parton distribution functions, we analyze the precision determination of Z-boson couplings to left-handed and right-handed u-quarks and d-quarks, and explore Beyond-Standard-Model contributions using the SMEFT framework. We comment on the role of the AFB asymmetry for the electroweak SMEFT fit and precision Z-boson physics at the LHC and high-luminosity HL-LHC.
Indico Link: https://indico.hep.ipm.ir/e/h.abdolmaleki2
Meeting Place: Seminar Room, School of Particles and Accelerators, IPM
Link to Join Virtually: https://meet.google.com/bda-vsem-tuv
Indico
Wednesday weekly meeting
General weekly meeting of the school of particles and accelerators (hybrid format) Meeting Place: Seminar Room, School of Particles and Accelerators, IPM Link to join virtually: https://meet.google.com/bda-vsem-tuv