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Mejora la medición de la forma del electrón
J J Hudson1, D M Kara, I J Smallman
1Centre for Cold Matter, Blackett Laboratory, Imperial College London, Prince Consort Road, London SW7 2AZ, UK.
Nature
|May 27, 2011
Resumen
Los científicos buscaron un momento dipolo eléctrico de electrones (EDM), un signo de una nueva física más allá del Modelo Estándar. El experimento no encontró evidencia de un electrón EDM, lo que indica que el electrón es esférico con una precisión sin precedentes.
Área de la Ciencia:
- * Física de las partículas.
- * La Mecánica Cuántica es la mecánica cuántica.
- * Astrofísica es la astrofísica.
Sus antecedentes:
- * El momento dipolo eléctrico (EDM) del electrón es una medida de su desviación de la simetría esférica.
- * El Modelo Estándar de la física de partículas predice un EDM de electrones extremadamente pequeño, muy por debajo de los límites actuales de detección experimental.
- * Las extensiones del Modelo Estándar y las teorías que abordan la asimetría materia-antimateria del Universo predicen EDM de electrones más grandes y potencialmente detectables.
Objetivo del estudio:
- * Buscar el momento dipolo eléctrico de electrones (EDM) con la mayor precisión hasta la fecha.
- * Para restringir la nueva física más allá del Modelo Estándar, en particular la supersimetría.
- * Para investigar la relación entre los EDM y la asimetría materia-antimateria en el Universo.
Principales métodos:
- * Se utilizaron moléculas polares frías para realizar mediciones de alta precisión.
- * Mide los desplazamientos de energía atto-electronvolt dentro de las moléculas.
- * Se emplearon técnicas experimentales de vanguardia para lograr una sensibilidad sin precedentes.
Principales resultados:
- * Se obtuvo una medición del electrón EDM: d(e) = (-2.4 ± 5.7(stat) ± 1.5(syst)) × 10−28 e·cm.
- * Se ha establecido un nuevo límite superior para el EDM de electrones: d e) sin < 10,5 × 10−28 e·cm con un 90% de confianza.
- * El resultado es consistente con cero, lo que indica que el electrón es esférico a este nivel de precisión.
Conclusiones:
- * La ausencia de un electrón detectable EDM impone restricciones estrictas a las teorías más allá del Modelo Estándar, incluyendo la supersimetría.
- * La medición explora la nueva física en la escala de energía tera-electronvolt.
- * Esta medición precisa contribuye a comprender las propiedades fundamentales de las partículas y los rompecabezas cosmológicos como el desequilibrio materia-antimateria.
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