Video Experimental Relacionado
Updated: May 6, 2026
07:45
Quasi-light Storage for Optical Data Packets
Published on: February 6, 2014
10.1K
Un cuásar luminoso con un desplazamiento al rojo de z = 7.0855
Daniel J Mortlock1, Stephen J Warren, Bram P Venemans
1Astrophysics Group, Imperial College London, Blackett Laboratory, Prince Consort Road, London SW7 2AZ, UK. mortlock@ic.ac.uk)
Nature
|July 2, 2011
Resumen
Los astrónomos descubrieron un cuásar (ULAS J1120+0641) en el corrimiento al rojo 7.085, ofreciendo nuevos conocimientos sobre el universo temprano. Este hallazgo ayuda a sondear el medio intergaláctico.
Área de la Ciencia:
- Cosmología Cosmología.
- La astrofísica es la astrofísica.
- Estudios del Universo Temprano Estudios del Universo Temprano
Sus antecedentes:
- El medio intergaláctico (IGM, por sus siglas en inglés) no se reionizó completamente hasta aproximadamente mil millones de años después del Big Bang.
- La observación de quásares con desplazamientos al rojo (z) > 6,5 es un desafío debido a las limitaciones de la exploración óptica.
- Estudios anteriores se basaron en cuásares con z < 6,5 para comprender la reionización.
Objetivo del estudio:
- Identificar y caracterizar quásares con desplazamientos al rojo más altos (z > 6.5) para sondear el IGM.
- Para investigar las propiedades del universo temprano y la época de reionización.
- Para entender la fracción neutral del IGM en el amanecer cósmico.
Principales métodos:
- Utilizó encuestas ópticas para identificar candidatos a cuásares de alto desplazamiento al rojo.
- Se han realizado observaciones espectroscópicas de ULAS J112001.48+064124.3 (z=7.085).
- Se analizó la luminosidad del cuásar, la masa del agujero negro y el radio ionizado de la zona cercana.
Principales resultados:
- Descubrió ULAS J1120+0641 con desplazamiento al rojo z = 7.085, lo que corresponde a 0.77 mil millones de años después del Big Bang.
- Se midió una luminosidad de 6.3 × 10^13 L () y una masa de agujero negro de 2 × 10^9 M ().
- Se observó un radio cercano a la zona de 1,9 megaparsecs, más pequeño de lo típico para z ~ 6.0-6.4 quásares.
- El perfil de transmisión de la zona cercana indica un ala de amortiguación de Lyα, lo que sugiere una fracción neutral > 0,1 en el IGM de primer plano.
Conclusiones:
- ULAS J1120+0641 proporciona una sonda crucial del IGM en z ~ 7.
- La pequeña zona ionizada cercana y el ala de amortiguación Lyα sugieren un hidrógeno neutro significativo en el IGM temprano.
- Este descubrimiento empuja la frontera observacional para el estudio de la época de reionización.
Videos de Conceptos Relacionados
02:39Emission Spectra
65.2K
When solids, liquids, or condensed gases are heated sufficiently, they radiate some of the excess energy as light. Photons produced in this manner have a range of energies, and thereby produce a continuous spectrum in which an unbroken series of wavelengths is present.
65.2K
01:21Schwarzschild Radius and Event Horizon
2.2K
No object with a finite mass can travel faster than the speed of light in a vacuum. This fact has an interesting consequence in the domain of extremely high gravitational fields.
The minimum speed required to launch a projectile from the surface of an object to which it is gravitationally bound so that it eventually escapes the object’s gravitational field is called the escape velocity. The escape velocity is independent of the mass of the object. Merging the idea of escape...
The minimum speed required to launch a projectile from the surface of an object to which it is gravitationally bound so that it eventually escapes the object’s gravitational field is called the escape velocity. The escape velocity is independent of the mass of the object. Merging the idea of escape...
2.2K
01:10Detection of Black Holes
1.7K
Although black holes were theoretically postulated in the 1920s, they remained outside the domain of observational astronomy until the 1970s.
Their closest cousins are neutron stars, which are composed almost entirely of neutrons packed against each other, making them extremely dense. A neutron star has the same mass as the Sun but its diameter is only a few kilometers. Therefore, the escape velocity from their surface is close to the speed of light.
Not until the 1960s, when the first neutron...
Their closest cousins are neutron stars, which are composed almost entirely of neutrons packed against each other, making them extremely dense. A neutron star has the same mass as the Sun but its diameter is only a few kilometers. Therefore, the escape velocity from their surface is close to the speed of light.
Not until the 1960s, when the first neutron...
1.7K
01:37Super-resolution Fluorescence Microscopy
12.3K
Super-resolution fluorescence microscopy (SRFM) provides a better resolution than conventional fluorescence microscopy by reducing the point spread function (PSF). PSF is the light intensity distribution from a point that causes it to appear blurred. Due to PSF, each fluorescing point appears bigger than its actual size, and it is the PSF interference of nearby fluorophores that causes the blurred image. Various approaches to achieving higher resolution through SRFM have recently been...
12.3K
01:29Atomic Emission Spectroscopy: Lab
881
AES is a powerful analytical technique, especially effective when used with plasma sources, producing abundant spectra in characteristic emission lines. The Inductively Coupled Plasma (ICP), in particular, yields superior quantitative analytical data due to its high stability, low noise, low background, and minimal interferences under optimal experimental conditions. However, newer air-operated microwave sources are emerging as promising alternatives that could be more cost-effective than...
881
01:24The Seven Crystal Systems: Overview
298
Crystals with various point group symmetries belong to different crystal classes, which are synonymous terms. Despite being in the same class, crystals may have distinct shapes, like cubes and octahedra. There are 32 three-dimensional point groups, all of which are systematically divided into seven crystal systems.The basic cubic crystal system, exemplified by NaCl, features orthogonal vectors (α = β = �� = 90°) of equal lengths (a = b = c). When specific...
298