A powerful and robust control system is a crucial, often neglected, pillar of any modern, complex physics experiment that requires the management of a multitude of different devices and their precise ...time synchronisation. The AEḡIS collaboration presents CIRCUS, a novel, autonomous control system optimised for time-critical experiments such as those at CERN’s Antiproton Decelerator and, more broadly, in atomic and quantum physics research. Its setup is based on Sinara/ARTIQ and TALOS, integrating the ALPACA analysis pipeline, the last two developed entirely in AEḡIS. It is suitable for strict synchronicity requirements and repeatable, automated operation of experiments, culminating in autonomous parameter optimisation via feedback from real-time data analysis. CIRCUS has been successfully deployed and tested in AEḡIS; being experiment-agnostic and released open-source, other experiments can leverage its capabilities.
Low-temperature antihydrogen atoms are an effective tool to probe the validity of the fundamental laws of Physics, for example the Weak Equivalence Principle (WEP) for antimatter, and -generally ...speaking- it is obvious that colder atoms will increase the level of precision.
After the first production of cold antihydrogen in 2002 1, experimental efforts have substantially progressed, with really competitive results already reached by adapting to cold antiatoms some well-known techniques pre- viously developed for ordinary atoms. Unfortunately, the number of antihydrogen atoms that can be produced in dedicated experiments is many orders of magnitude smaller than of hydrogen atoms, so the development of novel techniques to enhance the production of antihydrogen with well defined (and possibly controlled) conditions is essential to improve the sensitivity.
We present here some experimental results achieved by the AEgIS Collaboration, based at the CERN AD (Antiproton Decelerator) on the production of antihydrogen in a pulsed mode where the production time of 90% of atoms is known with an uncertainty of ~ 250 ns 2. The pulsed antihydrogen source is generated by the charge-exchange reaction between Rydberg positronium (
Ps*
) and an antiproton (
p¯
):
p¯
+
P
s
*
→
H¯
* +
e
−
, where
Ps*
is produced via the implantation of a pulsed positron beam into a mesoporous silica target, and excited by two consecutive laser pulses, and antiprotons are trapped, cooled and manipulated in Penning-Malmberg traps. The pulsed production (which is a major milestone for AEgIS) makes it possible to select the antihydrogen axial temperature and opens the door for the tuning of the antihydrogen Rydberg states, their de-excitation by pulsed lasers and the manipulation through electric field gradients.
In this paper, we present the results achieved by AEgIS in 2018, just before the Long Shutdown 2 (LS2), as well as some of the ongoing improvements to the system, aimed at exploiting the lower energy antiproton beam from ELENA 3.
New Physics Searches with Isotope Shifts of Two Hg Clock Transitions Witkowski, M.; Ciurylo, R.; Gogyan, A. ...
2022 Joint Conference of the European Frequency and Time Forum and IEEE International Frequency Control Symposium (EFTF/IFCS),
2022-April-24
Conference Proceeding
We present the experimental project of searching for physics beyond the Standard Model by looking for breaking of linearity in the King plot of two Hg clock transitions.
We report on laser cooling of a large fraction of positronium (Ps) in free flight by strongly saturating the 1 3 S − 2 3 P transition with a broadband, long-pulsed 243 nm alexandrite laser. The ...ground state Ps cloud is produced in a magnetic and electric field-free environment. We observe two different laser-induced effects. The first effect is an increase in the number of atoms in the ground state after the time Ps has spent in the long-lived 2 3 P states. The second effect is one-dimensional Doppler cooling of Ps, reducing the cloud’s temperature from 380(20) to 170(20) K. We demonstrate a 58(9)% increase in the fraction of Ps atoms with v 1 D < 3.7 × 10 4 m s − 1 . Published by the American Physical Society 2024
We report on laser cooling of a large fraction of positronium (Ps) in free-flight by strongly saturating the $1^3S$-$2^3P$ transition with a broadband, long-pulsed 243 nm alexandrite laser. The ...ground state Ps cloud is produced in a magnetic and electric field-free environment. We observe two different laser-induced effects. The first effect is an increase in the number of atoms in the ground state after the time Ps has spent in the long-lived $3^3P$ states. The second effect is the one-dimensional Doppler cooling of Ps, reducing the cloud's temperature from 380(20) K to 170(20) K. We demonstrate a 58(9) % increase in the coldest fraction of the Ps ensemble.
We report on laser cooling of a large fraction of positronium (Ps) in free flight by strongly saturating the 1^{3}S-2^{3}P transition with a broadband, long-pulsed 243 nm alexandrite laser. The ...ground state Ps cloud is produced in a magnetic and electric field-free environment. We observe two different laser-induced effects. The first effect is an increase in the number of atoms in the ground state after the time Ps has spent in the long-lived 2^{3}P states. The second effect is one-dimensional Doppler cooling of Ps, reducing the cloud's temperature from 380(20) to 170(20) K. We demonstrate a 58(9)% increase in the fraction of Ps atoms with v_{1D}<3.7×10^{4} ms^{-1}.
The 38 essays in this book look back at language experience as an educational approach, provide practical classroom applications, and reconceptualize language experience as an overarching education ...process. Classroom teachers and reading specialists describe strategies in use in a variety of classroom settings and describe ways to integrate current assessment techniques with the language experience approach. Essays in the book are: (1) "The Language Experience Approach: A Framework for Learning" (Nancy D. Padak and Timothy V. Rasinski); (2) "Focus on Language Experience Learning and Teaching" (MaryAnne Hall); (3) "Language Experience Approach: A British Perspective" (Robin Campbell); (4) "The History of Language Experience: A U.S. Perspective" (Jane L. Davidson); (5) "The Language Experience Special Interest Group (LESIG) of the International Reading Association: An Historical Overview" (Bonnie C. Wilkerson); (6) "Using Language Experiences in Beginning Reading: How a Language Experience Program Works" (Roach Van Allen); (7) "Making Written Language Meaningful" (MaryAnne Hall); (8); "Approaches to Environmental Print with Young Children" (Bobbie Gibson Warash, Mary W. Strong and Rachel N. Donoho); (9) "The Scrapbook Project" (Bobbie Gibson Warash and Diana J. Kingsbury); (10) "Developing Story Discourse: A Technique for Parents" (Lane Roy Gauthier and David B. Yaden); (11) "Guided Imagery as Language Experience" (Barbara J. Walker); (12) "Play as Story" (Kathleen Roskos); (13) "Using Nursery Rhymes with Early Experience Stories: A Language/Literature Program" (K. Eleanor Christensen and William J. Oehlkers); (14) "Linking Literacy and Lyrics through Song Picture Books" (Kathy Barclay); (15) "Beginning Writing: Where Does it Really Begin?" (Kathy Barclay); (16) "Using LEA to Assess Literacy in the Primary Grades" (Elizabeth Gibbons Pryor); (17) "Tying Assessment to Instruction: Adam Learns to Read the LEA Way" (Olga Nelson, Patricia A. Charles Kalmes and Elizabeth Hatfield-Walsh); (18) "My Experience with Language Experience" (Marilyn L. Fletcher); (19) "A First Grade Language Experience Teacher Talks about the Principles That Guide Her Practice and Decision Making" (Janice V. Kristo and Mary Giard); (20) "Language, Experience, and Learning: A Natural Connection for the Middle Grades" (Elizabeth G. Sturtevant); (21) "The Group Mapping Activity for Instruction in Reading and Thinking" (Jane L. Davidson); (22) "Awareness and Anticipation: Utilizing LEA and DR-TA in the Content Classroom" (Bonnie C. Wilkerson); (23) "Sorting: A Word Study Alternative" (Jean Wallace Gillet); (24) "The Directed Spelling Thinking Activity (DSTA): Providing an Effective Balance in Word Study Instruction" (Jerry Zutell); (25) "More Than Just a Brownie: Language Experience and Edible Science for the Middle Grades" (Ellen Lawrence Pesko); (26) "Williamsville: An Integrated Language Experience Approach to Math" (Patty Tarrant); (27) "Collecting, Writing, and Telling Family Folklore Stories" (Annette Nancy Taylor and Olga Nelson); (28) "Making History Memorable" (Carolyn Johns); (29) "LEA: Framework for Assessing Students' Higher-Level Thinking Skills" (Mary Elizabeth Kline); (30) "Is Anybody Really There? Developing Voice in Student Writing" (William J. Romeo); (31) "Language and Experience in the Middle School: The Power of the Writing Workshop" (N. Suzanne Standerford); (32) "LEA and Students with Special Needs" (Harvetta M. Robertson); (33) "Empowering Students with Learning Disabilities through Language Experience" (Sandra M. Stokes); (34) "ZPD+LEA=Reading for Special Needs Children: A Formula for Success" (Rose Anne Casement); (35) "Variations on a Theme: Using Thematically Framed Language Experience Activities for English as a Second Language (ESL) Instruction" (Kathleen A.J. Mohr); (36) "Literacy Development of Second Language Learners with Technology and LEA" (Vicki Parsons Duling); (37) "Negotiated Language Experience and Content Area Instruction in the Bilingual Classroom" (Linda Lewis-White); and (38) "The Language Experience Approach: Yesterday, Today, and Tomorrow" (Michael R. Sampson and Mary Beth Sampson). An appendix contains "A Chronology of the Language Experience Special Interest Group" by Bonnie C. Wilkerson. (RS)
Dual-Wavelength Ultra-Stable Optical Cavity Linek, A.; Munoz-Rodriguez, R.; Zawada, M. ...
2023 Joint Conference of the European Frequency and Time Forum and IEEE International Frequency Control Symposium (EFTF/IFCS),
2023-May-15
Conference Proceeding
We present the development of a dual-wavelength ultra-stable optical cavity operating at 1064 nm and 908 nm - the wavelengths that, after frequency quadrupling, correspond to Hg clock transitions at ...266 nm ( 1 S 0 - 3 P 0 ) and 227 nm ( 1 S 0 - 3 P 2 ). The cavity will be applied for precise spectroscopic measurements of clock lines of Hg atoms.
