Precision $e^-$ beam polarimetry at an $e^+e^-$ B factory using tau-pair events
Bibliographic record
Abstract
A novel technique for measuring the average beam polarization in e^+e^- <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow> <mml:msup> <mml:mi>e</mml:mi> <mml:mo>+</mml:mo> </mml:msup> <mml:msup> <mml:mi>e</mml:mi> <mml:mo>−</mml:mo> </mml:msup> </mml:mrow> </mml:math> collisions, known as Tau Polarimetry, has been developed by the BABAR collaboration. This technique makes use of the relationship between the polarization of the beams, the resulting polarization of the \tau^+\tau^- <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow> <mml:msup> <mml:mi>τ</mml:mi> <mml:mo>+</mml:mo> </mml:msup> <mml:msup> <mml:mi>τ</mml:mi> <mml:mo>−</mml:mo> </mml:msup> </mml:mrow> </mml:math> produced, and the kinematics of the decay products. Using this technique BABAR has measured the average e^- <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:msup> <mml:mi>e</mml:mi> <mml:mo>−</mml:mo> </mml:msup> </mml:math> beam polarization of PEP-II to be 0.0034 ± 0.0024_{stat} ± 0.0029_{sys} <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow> <mml:mo>±</mml:mo> <mml:msub> <mml:mn>0.0024</mml:mn> <mml:mrow> <mml:mi>s</mml:mi> <mml:mi>t</mml:mi> <mml:mi>a</mml:mi> <mml:mi>t</mml:mi> </mml:mrow> </mml:msub> <mml:mo>±</mml:mo> <mml:msub> <mml:mn>0.0029</mml:mn> <mml:mrow> <mml:mi>s</mml:mi> <mml:mi>y</mml:mi> <mml:mi>s</mml:mi> </mml:mrow> </mml:msub> </mml:mrow> </mml:math> . This technique is expected to be used at Belle II after a proposed polarization upgrade as the most precise method with which beam polarization can be determined.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.000 | 0.001 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".