error 404 on http://ppa.launchpad.net vivid/main amd64 Packages

Hi Ubuntu community

I install ubuntu 15.04 the last week, I move from xubuntu (14.04) to ubuntu 15.04 tring to check the new features and the enhances of the destkop.

Since yesterday I'm receiving the following errors when try to update my software and I don't know if this software sources are part of the core.

I already "clean" the catalog by running a rm -rf * on /var/lib/apt/lists.

the errors are:

nelsonj@nelsonj-Lenovo-G400s:~$ sudo apt-get update
......
Err http://ppa.launchpad.net vivid/main amd64 Packages
  404 Not Found
Err http://ppa.launchpad.net vivid/main i386 Packages
  404 Not Found
Get:21 http://co.archive.ubuntu.com vivid-updates/main amd64 Packages [196 kB]
Ign http://ppa.launchpad.net vivid/main Translation-en_US
Ign http://ppa.launchpad.net vivid/main Translation-en
.....

Fetched 1.265 kB in 28s (45,0 kB/s)
W: Failed to fetch http://ppa.launchpad.net/captiva/ppa/ubuntu/dists/vivid/main/binary-amd64/Packages 404 Not Found

W: Failed to fetch http://ppa.launchpad.net/captiva/ppa/ubuntu/dists/vivid/main/binary-i386/Packages 404 Not Found

E: Some index files failed to download. They have been ignored, or old ones used instead.