Sonic Mach Cones Induced by Fast Partons in a Perturbative Quark-Gluon Plasma

We derive the space-time distribution of energy and momentum deposited by a fast parton traversing a weakly coupled quark-gluon plasma by treating the fast part on as the source of an external color field perturbing the medium. We then use our result as a source term for the linearized hydrodynamical equations of the medium. We show that the solution contains a sonic Mach cone and a dissipative wake if the parton moves at a supersonic speed.Comment: Final version accepted for publicatio

Collision geometry fluctuations and triangular flow in heavy-ion collisions

We introduce the concepts of participant triangularity and triangular flow in heavy-ion collisions, analogous to the definitions of participant eccentricity and elliptic flow. The participant triangularity characterizes the triangular anisotropy of the initial nuclear overlap geometry and arises from event-by-event fluctuations in the participant-nucleon collision points. In studies using a multi-phase transport model (AMPT), a triangular flow signal is observed that is proportional to the participant triangularity and corresponds to a large third Fourier coefficient in two-particle azimuthal correlation functions. Using two-particle azimuthal correlations at large pseudorapidity separations measured by the PHOBOS and STAR experiments, we show that this Fourier component is also present in data. Ratios of the second and third Fourier coefficients in data exhibit similar trends as a function of centrality and transverse momentum as in AMPT calculations. These findings suggest a significant contribution of triangular flow to the ridge and broad away-side features observed in data. Triangular flow provides a new handle on the initial collision geometry and collective expansion dynamics in heavy-ion collisions.Comment: 8 pages, 8 figures, correction after publication, Fig8b has been corrected: The pt selection in AMPT calculation has been changed to match the selection in STAR dat

Personalized Professional Development Plans

Nancy Ruppert is the past-president of AMLE and past-president of NAPOMLE. She is the chair of the education department at UNC Asheville. Her current areas of interest are in advocating for middle school alumni and creating resources to advocate for middle level education. Here she invites readers to contribute to ideas for ongoing professional development

What Drives your Spirit and Commitment to Middle Level Education? Exploring a Middle School Mindset

Over the past two years, middle school advocates have been sharing their thoughts on the following prompt: “What drives your spirit and commitment to middle level education?” The purpose has been to capture ‘the spirit’ of middle school* educators?’ From these stories five characteristics emerged that can help us consider how to promote the next generation of middle school leaders. Perhaps using the findings from this exercise can help us advocate for the next generation of middle school leaders. * For the purpose of this study, middle school refers to those who work with 10-15 year olds and includes intermediate schools, a K-8, middle schools, junior highs, or 9th grade academies

Intrinsically Legal-For-Trade Objects by Digital Signatures

The established techniques for legal-for-trade registration of weight values meet the legal requirements, but in praxis they show serious disadvantages. We report on the first implementation of intrinsically legal-for-trade objects, namely weight values signed by the scale, that is accepted by the approval authority. The strict requirements from both the approval- and the verification-authority as well as the limitations due to the hardware of the scale were a special challenge. The presented solution fulfills all legal requirements and eliminates the existing practical disadvantages.Comment: 4 pages, 0 figure

Teaching Candidates to Assess Student Learning: A COVID Collaboration with Arts and Sciences Faculty

In the fall of 2020, due to COVID, our candidates did not have access to student work samples early in the semester. In order to learn how to assess student learning I reached out to an Arts and Sciences faculty who teaches a freshman course. The Arts and Science faculty was a former middle school teacher who was scheduled to talk about the teaching of writing in our methods class. We decided to add using work samples from her current students to provide an assessment experience. This exercise allowed candidates to create a one-point rubric, analyze student work, give feedback, examine patterns of learning for the whole class, as well as give suggestions for each student based on their work. The practice prepared them for their own fall teaching assignment and all were able to analyze their students\u27 works successfully

Collaboration in the Middle: Middle Grades to Higher Education Promoting, Advocating, Igniting Support for Middle Schools

The authors provide an overview of the Southeast Professors of Middle Level Education Symposium, which was held in Greenville, SC, May 17-18, 2018. This is the introduction to the proceedings from the Symposium

Celebrating 25 Years of the National Association of Professors of Middle Level Education

The National Association of Professors for Middle Level Education has been focused on middle grades education since 1997. This is an introduction for the CIMLE Journal in celebration of NAPOMLE\u27s 25 anniversary in 2022

What does the rho-meson do? In-medium mass shift scenarios versus hadronic model calculations

The NA60 experiment has studied low-mass muon pair production in In-In collisions at $158 {\rm AGeV}$ with unprecedented precision. With these results there is hope that the in-medium modifications of the vector meson spectral function can be constrained more thoroughly than before. We investigate in particular what can be learned about collisional broadening by a hot and dense medium and what constrains the experimental results put on in-medium mass shift scenarios. The data show a clear indication of considerable in-medium broadening effects but disfavor mass shift scenarios where the $\rho$-meson mass scales with the square root of the chiral condensate. Scaling scenarios which predict at finite density a dropping of the $\rho$-meson mass that is stronger than that of the quark condensate are clearly ruled out since they are also accompanied by a sharpening of the spectral function.Comment: Proceeding contribution, Talk given by J. Ruppert at Workshop for Young Scientists on the Physics of Ultrarelativistic Nucleus-Nucleus Collisions (Hot Quarks 2006), Villasimius, Sardinia, Italy, 15-20 May 2006. To appear in EPJ