1 E-18 s
Encyclopedia
An attosecond is an SI
unit of time equal to 10−18 of a second
. (one quintillionth of a second
). For context, an attosecond is to a second what a second is to about 31.71 billion years, or twice the age of the universe.
The word "attosecond" is formed by the prefix
atto and the unit second. Atto- was made from the Danish word for eighteen (atten). Its symbol is as.
An attosecond is equal to 1000 zeptoseconds, or 1/1000 of a femtosecond. Because the next higher SI unit for time is the femtosecond (10−15 seconds), durations of 10−17 s and 10−16 s will typically be expressed as tens or hundreds of attoseconds:
Si
Si, si, or SI may refer to :- Measurement, mathematics and science :* International System of Units , the modern international standard version of the metric system...
unit of time equal to 10−18 of a second
Second
The second is a unit of measurement of time, and is the International System of Units base unit of time. It may be measured using a clock....
. (one quintillionth of a second
Second
The second is a unit of measurement of time, and is the International System of Units base unit of time. It may be measured using a clock....
). For context, an attosecond is to a second what a second is to about 31.71 billion years, or twice the age of the universe.
The word "attosecond" is formed by the prefix
SI prefix
The International System of Units specifies a set of unit prefixes known as SI prefixes or metric prefixes. An SI prefix is a name that precedes a basic unit of measure to indicate a decadic multiple or fraction of the unit. Each prefix has a unique symbol that is prepended to the unit symbol...
atto and the unit second. Atto- was made from the Danish word for eighteen (atten). Its symbol is as.
An attosecond is equal to 1000 zeptoseconds, or 1/1000 of a femtosecond. Because the next higher SI unit for time is the femtosecond (10−15 seconds), durations of 10−17 s and 10−16 s will typically be expressed as tens or hundreds of attoseconds:
- Shorter times
- 1 attosecond – the time it takes for light to travel the length of three hydrogen atoms.
- 12 attoseconds – record for shortest time interval measured as of May 12, 2010.
- 24 attoseconds – the atomic unit of time.
- 80 attoseconds – the shortest pulses of laser light yet created.
- 100 attoseconds - fastest ever view of molecular motion
- 200 attoseconds (approximately) – half-life of beryllium-8Isotopes of berylliumAlthough beryllium has 12 known isotopes, only one of these isotopes is stable and a primordial nuclide. As such, it is considered a monoisotopic element. It is also a mononuclidic element, because its other isotopes are short-lived that none are primordial and their abundance is very low...
, maximum time available for the triple-alpha processTriple-alpha processThe triple alpha process is a set of nuclear fusion reactions by which three helium-4 nuclei are transformed into carbon.Older stars start to accumulate helium produced by the proton–proton chain reaction and the carbon–nitrogen–oxygen cycle in their cores...
for the synthesis of carbon and heavier elements in stars. - 320 attoseconds – estimated time it takes electronElectronThe electron is a subatomic particle with a negative elementary electric charge. It has no known components or substructure; in other words, it is generally thought to be an elementary particle. An electron has a mass that is approximately 1/1836 that of the proton...
s to transfer between atomAtomThe atom is a basic unit of matter that consists of a dense central nucleus surrounded by a cloud of negatively charged electrons. The atomic nucleus contains a mix of positively charged protons and electrically neutral neutrons...
s.
- Longer times